44 years ago, Darlene Avis Geertsema 'went to visit a sick friend'. She hasn't been seen since.

Content warning: This story involves family violence and murder and may be triggering to some readers.

Each year, more than 38,000 missing person reports are received by Australian police. Most people are found within a short period of time. But, as of right now, there are about 2,600 long-term missing persons - those who are missing for more than three months.

Darlene Avis Geertsema is one of them.

The 30-year-old went missing on October 23, 1978, nearly 44 years ago. She has not been seen or heard from since that day.

Darlene left behind family and friends who she loved, and who loved her dearly - including her six children.

The trail for Darlene's whereabouts went cold not long after her disappearance. It was not until July 2013, when then Detective Senior Constable Felicity Boyd - who has since been promoted to Sergeant - was assigned Darlene's case, that momentum picked up once again.

Sergeant Boyd carried out a comprehensive review of the case, including obtaining statements from witnesses, family, friends, and retired investigators, executing search warrants and reviewing original files. This led to an inquest in December of last year.

Here is everything we know.

Who is Darlene Avis Geertsema?

Darlene was born in Tasmania on November 29, 1947. Her parents, who have since passed away, were Leonard and Elizabeth (nicknamed Betty) Styles.

Darlene met Siert Fokko Geertsema on King Island in Tasmania and the pair married on April 2, 1965. They were both young - she was only 17 and Siert was 19. Darlene soon gave birth to twins Elizabeth and Tania, and the family moved to Victoria for Siert's job. 

In 1968, Darlene gave birth to her third child, Robyn. Not long after, the family of five moved back to Tasmania, again for Siert's work. Sharon, their fourth daughter, was born in 1969.

A few months later, Siert was sent to jail for three months for burglary. While he was incarcerated, Darlene began a brief relationship with another man and fell pregnant with her fifth child, Kathryn, who was born in 1970.

Siert and Darlene broke up soon after, likely due to her affair. They remained on good terms however, and six months after separating, Siert tried to rekindle their relationship. But by that time, Darlene had moved on with another man.

Mamamia will not name this man for legal reasons as he is a person of interest. For the purpose of this story, we will call him Mr POI.

Siert spoke with Darlene, and she told him that although Mr POI "bashed her" she still loved him. Recognising their relationship was over for good, Siert gave her $2000; this was all his savings, which was a lot of money for that time. He then left and relocated to the Northern Territory for work.

Darlene, her five daughters, and Mr POI moved from house to house and state to state in the early 70s. 

"Her relationship with the person of interest became quite strained, and she was unsettled through that relationship. It wasn't an exclusive relationship, but it was certainly recognised as an on-off relationship," Sergeant Boyd tells Mamamia. "And that on-off relationship lasted for around seven years up until the time that she disappeared."

In 1972, Darlene gave birth to her sixth and final child, a son named Ryan. Mr POI was Ryan's father.

Having six children under the age of 11 was hard on Darlene. She struggled to adequately care for and control them all, and financially support them. In 1975, the four oldest children - Tania, Elizabeth, Robyn and Sharon - went to live with Siert, their father, in Queensland.

"It would have been a very difficult decision for her to separate from her children. But after speaking with the ex-husband, and speaking with the children, and speaking with Darlene's siblings, [we know] she never forgot a birthday. She loved to write letters to her children and their extended family doctor and she was a very family-orientated person. She was described as a very good mother," Sergeant Boyd says.

"Unfortunately, despite all these wonderful characteristics that have been provided from the family members, she's disappeared without a trace."

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When was the last time anyone saw Darlene?

On October 23, 1978 - a Monday - Darlene disappeared from her home at 58B Best Street in Devonport, Tasmania where she had been living with her two youngest children - Kathryn, eight, and Ryan, five.

According to Mr POI, Darlene was last seen leaving her home at 10.30pm in her 1977 red Holden Sunbird.

There's some conjecture on whether Mr POI was living at Best Street with the family at the time, but it's known that he was working as a bushman and that he had access to some alternate accommodation.

According to Mr POI, Darlene was going to drive to visit her sick friend Julie at 10.30 that night. Julie lived in Parkham, a small remote country town that is 35 minutes east of Devonport.

"It also appears, according to the person of interest, that Darlene was in a distressed condition, and that she'd been drinking alcohol, which was out of character for her. It was a Monday night and the children had been at school that day. And she was acting quite out of character," Sergeant Boyd says.

"According to the person of interest, Darlene had disclosed to him that she was in fact pregnant and had been diagnosed with cancer."

Mr POI claimed he searched for Darlene the next day, after she didn't return home that night. He travelled all over the northern part of the state and looked in places where he suspected she might be.

Two days after her disappearance, on Wednesday, October 25, Mr POI woke up and remembered that Darlene used to take the children to a park in Devonport. He drove down to Devonport and found Darlene's car locked and abandoned in a car park on Victoria Parade.

He then reported her missing to police.

In an affidavit tendered at the inquest, the Sergeant who took the report that day stated, "Something about the matter was odd and I later passed this on to Devonport CIB which at that time consisted of Detective Sergeant Max Bryan [now deceased] and Detective Sergeant Ashley Childs [also now deceased]... I can’t recall exactly who I spoke with but [Mr POI's] demeanour concerned me. He displayed no emotion. I thought this was strange."

After Darlene's disappearance was reported, a large stretch of foreshore where her car was discovered was searched, but it yielded no results.

Darlene's GP, Dr Wood, told investigators she was not pregnant and had no terminal illnesses. He said she was a reasonable, stable woman emotionally, and he thought it was very strange that she would have just left her children. He also said Darlene had been "bright and cheerful" when he last saw her on Monday, October 23, 1978 - the day she disappeared.

To add to that, her eldest children - the twins - were turning 13 that very day.

"So there was no evidence to support theories that Darlene had left the state or committed suicide," Sergeant Boyd says. "Detectives just weren't able to locate Darlene nor that were they able to ascertain a motive for why she disappeared."

After Darlene's disappearance, there were a number of inquiries conducted over several months. People were interviewed and areas were searched. Information was sought from members of the public.

There was a mistaken sighting of Darlene around Christmas in 1978, where it was thought that she appeared in the background of a current affairs programme that had aired on television. The Tasmanian police worked with the Victorian police to track the woman on television down, and she was identified as someone else other than Darlene.

At that time, Mr POI was not considered a person of interest.

"Interestingly, [investigators] did consider potentially a line of inquiry regarding foul play. There was certainly no evidence through the file that she had been the subject of foul play at that point in time," Sergeant Boyd says.

"But I think what really drove that home was Darlene's grandmother, who unfortunately is obviously now deceased. She voluntarily approached a police officer and provided that police officer with a black-and-white photograph of Darlene. And she disclosed to the police officer that she was very concerned about Darlene and was not convinced that she has just left. And that [the police] should probably look a little bit closer at her relationship with the person of interest.

"And I think that voluntary approach from Darlene's grandmother, who we understand that she was quite close with at the time, most likely directed the investigation somewhat towards some consideration of foul play. But there was certainly nothing that gave police any further grounds to consider that anyone had been involved in her disappearance at that time."

What are the recollections from the children of the night their mother disappeared?

Neither Kathryn nor Ryan were interviewed in 1978. Family and domestic violence was treated very differently at that time.

"Back then, there was certainly no legislation and protective orders like we have now. We've got massive government frameworks and funding to really support persons that are affected by family violence, including their children, in contemporary policing, and it's a really, really good thing that that's happening," Sergeant Boyd says.

In 2013, 35 years after Darlene's disappearance, statements were taken from Kathryn and Ryan about what they remembered about the last day they saw their mother.

"The night/day of my mother’s disappearance, I will tell it like I remember it. My mother picked up Ryan and me from the Devonport Primary School, which we had just started attending," Kathryn recalled in her statement.

"In my mother’s Red Sunbird Turano, I was sitting in the front seat and Ryan in the back seat. My mother showed me how airline tickets and the gifts she had brought for the girls, Tanya and Elizabeth for their 13th birthday. My mother, Ryan and I were so excited to be going to Queensland to see them. My mother stopped on the way home to the flat and got fish and chips for tea, as it was one of my favourite meals.

"When we got back to the flat, we sat down to our tea of fish and chips. I noticed that my mother was drinking out of her crystal horse and cart whiskey ornament. My mother looked and was acting very nervous. [Mr POI] came over and my mother put Ryan and I to bed. Ryan and I heard my mother and [Mr POI] having a very heated argument. I came out of my room to check on my mother as I had always done in the past, but I was sent back to my room as usual.

"The arguing got worse and I could hear hitting sounds. Not long after, there was dead silence and no noise or movement. The next thing I heard was the front door slam and the car lights shining through my bedroom window. I know that I would have been looking out of my bedroom window to see whose car it was driving off. I just can’t see anything in my mind, but I know I would have been looking. Ryan was upset. I kept going back to him and cuddling him. Still no sound in the flat, only Ryan crying for mum.

"I can’t remember looking around the flat to see if anyone was home, but I know I would have had a look at the time. Not long after the first car left, about half an hour or so later, a second car drove off. I can’t remember the rest of the time Ryan and I were left alone."

Ryan's statement did not recall anything related to family violence that night, but he too stated his mum was acting quite strange - she was nervous and drinking alcohol. She never did that.

Darlene's car. Image: Supplied.

What further evidence was there of family violence?

As the statements continued to come in during Sergeant Boyd's review and investigation, it became apparent Darlene had been a victim of family violence whilst in the relationship with Mr POI.

And that she wasn't the only one.

"So, as part of the investigation, we looked more broadly into the person of interest, and particularly in relation to intimate relationships that he had held that we could find," Sergeant Boyd says.

It was found that Mr POI grew up in the Westbury Deloraine area, and that he married his first wife in 1967, when he was 20 years old. He married her after he found out that she had fallen pregnant out of wedlock and wanted to give her child a name. His wife gave birth to her child, and in 1969, she gave birth to another child - Mr POI's first biological child.

"What we know is that throughout that relationship, there are allegations of family violence occurring. And as a result of the level of violence that was committed in that relationship, their marriage ended in 1969. Not that long after the son was born," Sergeant Boyd says.

"His first wife went and sought support and refuge from her parents at the time, and lived in the house with the children until she was able to find herself some accommodation, and stand on her feet and be the mother that she needed to be.

"So then we segue into the relationship with [Darlene and Mr POI], which as I say, the evidence has clearly established since 2013 that there was a level of family violence committed by the person of interest on Darlene.

"And we know now that he is married to his wife, and we were able to establish that there was some level of violence happening in that relationship very, very early on as well by speaking with her. So it appears that over a 13 year period, the person of interest perpetrated a level of family violence against these three women."

What stood out to Sergeant Boyd when Darlene's file first crossed her desk?

Sergeant Boyd has always been an inquisitive person. That's what drew her to policing and investigations in the first place.

"You definitely see the worst of people. But you also get to see the best of people. It's just interesting to learn what make makes people tick and why they do the things they do. And it is also satisfying to hold perpetrators to account for their behaviours as well. So I think I was just fortunate that this investigation fell on my desk... I certainly didn't seek it out," she says.

"But I've got a very strong moral code. And I can honestly say that this has strengthened over my 18 years of policing. Integrity in policing is really, really important as well; it holds me to account. I just do my best to question, seek and find - it doesn't matter what type of investigation it is. It's really paramount to remain objective, and let the evidence do all the talking. And you just need to ask questions, and you just need to question questions as well."

Sergeant Boyd acknowledges that over time, the way in which police treat missing person cases has considerably.

"I think police back in 1978 really only were able to work in the confines of the procedures in the legislation that were available to them then," she tells Mamamia.

This meant that the Sergeant had to basically start from the beginning and take a good look at everything that was reported at the time.

"One of the things that really stood out to me was the fact that the person of interest has provided information in the statement, when he reported Darlene missing, that they had separated for a period of time leading up to her disappearance, and then had decided to get back together again...," she says.

"The person of interest has informed police in his statement that they moved to Davenport for a couple of reasons. They obviously got back together again, and had made a decision that they were going to move to Davenport and live in this little unit for a short period of time so they could save enough money up so they could relocate to the mainland and make a go of it over there. So there was some talk around the fact that Darlene and the children and the person of interest were planning to live a life outside of Tasmania.

"What was also interesting was the person of interest also mentioned that another reason why they moved to Devonport was to distance themselves from another fellow that Darlene had been intimate with for about three months leading up to her disappearance. The person of interest has stated that this fellow that she'd been intimate with wanted to live with Darlene, but that she didn't want to live with him."

But there was a letter on file that struck Sergeant Boyd as contradictory to what Mr POI said in his statement. It was a letter from Darlene's mother, dated October 23 - the day Darlene disappeared. So, sadly, she never got to read it.

The police intercepted the letter when they were searching for Darlene and searched the family home. It appeared that the letter was in response to previous communications that had been going on between Darlene and her mother, and it was very clear in that letter that Darlene was planning to relocate to the mainland - but there was no mention at all of Mr POI.

During the inquest, other family members and friends also spoke about Darlene's future intentions to leave Tasmania with her children - none of her plans involved Mr POI.

"I just repeatedly found myself asking, why would a 30-year-old mother of six children, who had intentions of relocating to the mainland, just disappear, and permanently abandon her two youngest children, who were five and eight at the time? It just didn't make sense to me," Sergeant Boyd says.

"That was probably the paramount question that was just still sitting in the forefront of my mind."

What has the inquest into Darlene's disappearance found?

The inquest was held in December 2021 and the findings were handed down in June this year. In the report, the coroner looked at the four possibilities of what could have happened to Darlene: suicide, misadventure, left the state and died later, or homicide.

The first three possibilities were thoroughly vetted and thrown out.

That left the last possibility. The last probability - homicide.

In summary, the inquest found that Mr POI was the responsible for Darlene's death and disappearance. The evidence against him - his history of intimate violence, his frequent arguments with Darlene, his drinking, his knowledge of the bush, his access to a vehicle on the night, him being the last person to see her, his changing statements over the years, and compelling witness statements - pointed to the inevitable conclusion.

"For all these reasons I am satisfied to the requisite legal standard that Ms Geertsema died as a result of injuries inflicted upon her by [Mr POI] on the evening of October 23, 1978 at 58B Best Street, Devonport," the coroner's inquest statement revealed.

"I cannot determine on the evidence whether she died at that address or somewhere subsequent. I cannot determine the nature of those injuries. I cannot determine on the evidence the pathological cause of her death nor what became of her body."

And that is the saddest part - that still, after all these years, Darlene remains lost.

"Unfortunately, we still haven't been able to find her," Sergeant Boyd says. "We don't know how she died. The coroner couldn't find that out through the evidence that was given."

Even though the inquest ruled that Mr POI was the person responsible, the formal process of laying charges is separate. Charges have not yet been laid against POI or anyone else.

What can the public do to help Darlene's family find closure?

Due to the relationships she has built with Darlene's family and friends over the almost 10 years since picking up the case file, the Sergeant is able to speak a little to the trauma they have, and continue to go through.

"I think Darlene's loved ones would really support me in saying that they've each struggled in their own way. And after 44 years, it really must take a toll on them," she says. "Regardless where the evidence led me, it was absolutely apparent that Darlene loved to stay in touch with her sisters, and her mother, and her children, her ex-husband; she wrote to them often.

"And despite the fact that her four eldest children and the majority of her family were living interstate, she just thought the world of everyone, and more so her children. Unanimously, the family agree, there is no way that she would have ever intentionally planned to leave her children. Many of the children gave evidence at the inquest. And it was clear, after all this time, that they're still angry and sad and conflicted. And that's absolutely understandable.

"Unfortunately Darlene's mother is deceased, and also her sister. Friends have passed away as well over the course of the review. And quite sadly, and very recently, one of her daughters passed away the week before the coroner handed down his findings.

"There's so many people that have been affected in so many ways, and they've never actually been able to get to the point where we did in December last year, and provide their evidence and provide their memory, and be a voice for Darlene."

Things were particularly difficult for youngest daughter, Kathryn.

In the weeks after her mother disappeared, Kathryn was moved into alternative care by Mr POI (presumably because she was not his biological daughter), rather than being sent to Queensland to live with her four sisters. She had not only lost her mother so suddenly, but she was also separated from her brother and all the family she knew; all this at just eight years old.

Darlene's daughter, Kathryn. Image: Supplied.

"The family has been affected on so many levels for 44 years now. Over time and as other witnesses have been identified, people have just been dragged into these investigations because of the actions of one person. So for the family's sake, we just want to know where Darlene is, and we want to bring her home, so they have that level of closure," Sergeant Boyd tells Mamamia.

"In November last year, I announced a $500,000 reward to anyone in the community who can who could provide credible information... and that $500,000 remains in play. So I certainly at this point in time want to thank the community for the information that they've already provided. We've acted on that information. We've searched areas of interest but we haven't found Darlene yet.

"I remain very confident still that there is someone out there in our community who knows exactly what happened to her that night. And I'm really urging that person to please come forward and speak with us. It's about getting to the truth.

"The family deserve answers. It's been 44 years. And as a community, not just as police, but as a whole community, we owe it to that family to find those answers."

Help find Darlene: A $500,000 reward is on offer to anyone with credible information that can help police find Darlene and uncover the truth about what happened to her the night she disappeared. Anyone with information is asked to contact Crimestoppers on 1800 333 000.

National Missing Persons Week runs from July 31 to August 6. You can find more information on missing persons in Australia here.

If this post brings up any issues for you, or if you just feel like you need to speak to someone, please call 1800 RESPECT (1800 737 732) – the national sexual assault, domestic and family violence counselling service. It doesn’t matter where you live, they will take your call and, if need be, refer you to a service closer to home.

You can also call safe steps 24/7 Family Violence Response Line on 1800 015 188 or visit safesteps.org.au for further information.

The Men’s Referral Service is also available on 1300 766 491 or via online chat at ntv.org.au. 

You can also access the Are You Safe At Home's website service directory.

If you think you may be experiencing depression or another mental health problem, please contact your general practitioner. If you're based in Australia, 24-hour support is available through Lifeline on 13 11 14 or beyondblue on 1300 22 4636.