A violent husband, four marriages and 14 dogs: The dark days of Doris Day we didn't see.

Warning: This post deals with domestic violence and could be triggering for some readers.

The world is mourning Hollywood legend Doris Day, who passed away after a serious case of pneumonia, aged 97.

The actor died early on Monday at her home in Carmel Valley, California, surrounded by close friends, the Doris Day Animal Foundation confirmed.

The honey-voiced singer and actor, whose film dramas, musicals and innocent sex comedies made her a top star in the 1950s and 1960s, was among the most popular screen actresses in history.

Off screen, Day was a passionate animal rights advocate. She was married four times, divorced three and had one son, Terry Melcher who died in 2004.

In March of 1941, Day wed trombonist Al Jorden. She was just starting her career, and a year earlier had signed on to perform with Barney Rapp’s band which regularly performed in her home of Cincinnati.

At first, a 16-year-old Day was not interested in Jorden, seven years her senior. He asked her out and she turned him down - describing him to her mother as a "creep".

But Jorden was persistent and eventually Day agreed to go on a date with him. She fell for him, and in 1941 they said "I do".

In her 1973 autobiography, Day wrote about the moment she realised the man she married was abusive.

Just two days after the wedding, Jorden grew furious after he saw her giving a bandmate a kiss on the cheek to thank them for a wedding present. It was then that he struck her for the first time.

The abuse continued - even after Day discovered she was pregnant. Jorden wanted her to get an abortion, but Day refused and he beat her in an attempt to induce a miscarriage.

On February 8, 1942, Day gave birth to their son Terry.

Day kicked her abusive husband out of their home in 1943 and filed for divorce. Jorden took his own life in 1967.

As Day's career began to take off, she married George Weidler, a saxophonist and brother of child actress Virginia Weidler, but they divorced three years later.

After Weidler, Day revealed in her autobiography that she briefly dated future US President Ronald Reagan while they starred in the 1951 film Storm Warning.

"There were two things about Ronnie that impressed me," she wrote. "How much he liked to dance and how much he liked to talk. Ronnie is really the only man I've ever known who loved dancing. He danced well and he had a pleasant personality, so I invariably enjoyed going out with Ronnie."

On Day's 29th birthday - April 3, 1951 - she married manager Martin Melcher who officially adopted her son Terry.

Day wrote that for the most part, she was happy in her third marriage: "I seemed to have found the solid, serene life I had been seeking."

But after Melcher died in 1968, Day learned that for 17 years he and his business partner Jerome Rosenthal had been squandering away her fortune.

Of the betrayal, Day said she was mystified by Melcher's actions, as "this man who had slept with me, adopted my son, managed my career and business life".

Day was eventually awarded over $22 million for fraud and malpractice.

Day's fourth marriage, from April 14, 1976 to April 2, 1982, was to Barry Comden, the maître d at one of her favourite restaurants.

A known animal lover, Comden endeared himself to Day by giving her a bag of meat scraps and bones for her dogs - but he ultimately blamed her pets for the end of their marriage.

When their marriage broke down, Comden complained to the London Sunday Mail in 1996 that Day loved her "animal friends" more than she loved him.

"She had 14 dogs, and the final straw was when I was kicked out of bed to make way for Tiger, a poodle," he said.

In her autobiography, Day described just how much solace she found in the company of animals.

"I have found that when you are deeply troubled, there are things you get from the silent devoted companionship of a dog that you can get from no other source."

Her namesake animal foundation announced her death on Monday, stating that Day had been in excellent physical health until contracting pneumonia.

The foundation also said she requested "no funeral or memorial service and no grave marker".

Paul McCartney paid tribute to his friend following the news, calling Day "a true star in more ways than one".

"Visiting her in her Californian home was like going to an animal sanctuary where her many dogs were taken care of in splendid style," he said in a statement.

"She had a heart of gold and was a very funny lady who I shared many laughs with."

If this post brings up any issues for you, or if you just feel like you need to speak to someone, please 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.