Spencer, 57, was spotted at Williams’ home in California at around 11am on Tuesday morning, RadarOnline reports.

“She went into the house for a few minutes before someone in the house let her out of the garage and she left quickly,” an eyewitness told Radar.

She reportedly returned to her own home nearby around 4.30pm the same day, and neighbours have confirmed she has been going to Williams’ home since he he was found dead.

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Her identity comes after she posted a photo of Williams on her public Facebook account.

Above it she wrote: “What a time we had!”

Her Facebook account also has an older photograph of her and Williams (above) as her profile picture.

Spencer has been an assistant to Williams for around 20 years, has helped him on many of his Hollywood hit films including Happy Feet Two, Old Dogs, Night at the Museum, Night at the Museum 2, Insomnia, Jumanji, Patch Adams, The Birdcage, What Dreams May Come, Flubber, Father’s Day, Mrs Doubtfire and many more.

Spencer’s word’s come after Williams’ three children and former wife of have released separate statments about his death as it emerges his wife thought he was sleeping in.

Williams, 63, took his own life by hanging himself at his San Francisco Bay Area home but did not leave a suicide note, sheriff’s officials say.

Williams was found in a bedroom by his personal assistant on Monday at hisTiburon, California home, said Marin County Sheriff’s Lieutenant Keith Boyd at a press conference overnight.

Toxicology tests will be performed and the investigation is ongoing, Mr Boyd said.

Sheriff’s officials said Monday a preliminary investigation determined the cause of death was suicide due to asphyxia.

They also said it was the second time he had attempted suicide in the hours before his death.

His only daughter Zelda, from his second marriage, said Williams “was always warm, even in his darkest moments”.

She revealed that the last time she saw her father was on his birthday last month.

“I will be forever grateful that my brothers and I got to spend that time alone with him, sharing gifts and laughter,” she said.

“While I’ll never, ever understand how he could be loved so deeply and not find it in his heart to stay, there’s minor comfort in knowing our grief and loss, in some small way, is shared with millions.”

While many people have been sending love and support to the family, she suggested others may not have been so kind.

“As for those who are sending negativity, know that some small, giggling part of him is sending a flock of pigeons to your house to poop on your car. Right after you’ve had it washed. After all, he loved to laugh too,” she said.

Later today, she tweeted she would be off social media for a while, possibly forever.

Her Australia boyfriend and actor Jackson Heywood also tweeted his thanks to everyone who had sent messages of support today.

Cody Williams, also from Williams’ second marriage, released a statement describing the immense respect he had for this father.

“I will miss him and take him with me everywhere I go for the rest of my life, and will look forward, forever, to the moment when I get to see him again,” he said.

Zelda and Cody’s mother, Marsha Garces Williams, described the utter devastation the family are feeling.

“My heart is split wide open and scattered over the planet with all of you... My arms are wrapped around our children as we attempt to grapple with celebrating the man we love, while dealing with this immeasurable loss,” she said.

Williams eldest son, Zachary, from his first marriage to Valerie Velardi, said he lost a father and a best friend.

“I would ask those that loved him to remember him by being as gentle, kind, and generous as he would be. Seek to bring joy to the world as he sought,” he said.

Ben Affleck, star and co-writer of Good Will Hunting — the film that won Williams an Oscar — spoke of his sadness in posts on Facebook and Twitter.

“Heartbroken,” Affleck wrote. “Thanks chief - for your friendship and for what you gave the world. Robin had a ton of love in him. He personally did so much for so many people. He made Matt and my dreams come true. What do you owe a guy who does that? Everything. May you find peace my friend.”

At the Everett Theatre in Middletown, Delaware, where Dead Poets Society was filmed, locals who worked as extras on the film placed floral tributes in honour of the star.

Williams had suffered for years from periodic bouts of substance abuse and depression. He had talked openly about his difficulties with substance abuse and had sought treatment in the months before his death.

Williams’ press representative Mara Buxbaum said the actor had been battling severe depression recently. Just last month, he announced he was returning to a 12-step treatment program to work on his sobriety.

Coroner’s officials say the Oscar-winner was last seen alive at home around 10pm local time by his wife Susan Schneider on Sunday.

The next day she left home about 10.30am to take care of some errands thinking her husband was still sleeping in the other room.

Shortly before noon on Monday, the Sheriff’s Department received an emergency call from the home.

A multi-talented actor famed for his comedic genius, Williams won an Oscar for his work on Good Will Hunting, and also starred in hits Mrs. Doubtfire and Good Morning, Vietnam. He first rose to fame as a lovable alien Mork on hit sitcom Mork & Mindy.

However, Williams made reference to his substance abuse and depression in his comedy routines, including when he sought treatment in 2006 after a relapse that followed 20 years of sobriety.

Williams joked about that fall off the wagon during a comedy tour, saying: “I went to rehab in wine country to keep my options open.”

Reports have emerged that Williams was facing serious money troubles. A neighbour who saw him in the days before his death said he “was a shell” who looked “drawn and thin”.

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In September last year, Williams admitted he was forced to return to TV acting after three decades and sell his $35 million house because his two costly divorces left him on the verge of bankruptcy.

“The idea of having a steady job is appealing,” Williams told Parade magazine of his role in new TV show, The Crazy Ones.

“There are bills to pay. My life has downsized, in a good way. I’m selling the ranch up in Napa. I just can’t afford it anymore.

“Divorce is expensive. I used to joke they were going to call it ‘all the money’, but they changed it to ‘alimony’. It’s ripping your heart out through your wallet,” Williams said.

His wife Susan Schneider released this statement following her husband’s death:

“This morning, I lost my husband and my best friend, while the world lost one of its most beloved artists and beautiful human beings. I am utterly heartbroken. On behalf of Robin’s family, we are asking for privacy during our time of profound grief. As he is remembered, it is our hope the focus will not be on Robin’s death, but on the countless moments of joy and laughter he gave to millions.”

Williams has been married three times and has three children to two different mothers.

His first marriage was to Valerie Velardi, whom he married in 1978. They have one child, Zachary Pym, who was born in 1983. The pair divorced in 1988.

In 1989 he married his son’s nanny Marsha Garces, who was already pregnant with his daughter Zelda Rae. Their son Cody Alan, was born two years later in 1991. They divorced in 2008.

Williams married his current wife, graphic designer Susan Schneider on October 23, 2011.

Williams leaves behind four upcoming movies in the wake of his tragic death.

The actor wrapped filming on Night at the Museum: Secret of the Tomb, the third instalment in the franchise, in May. Williams reprised his role as Teddy Roosevelt in the film, which is due for release in December.

He shared the trailer with his 1.08 million Twitter followers on July 31, saying: “First look at the new “Night at the Museum Secret of the Tomb” I hope you enjoy it!”

Williams’ other holiday flick is Merry Friggin’ Christmas which will be released in November.

Dito Montiel drama Boulevard is also due for theatrical release having debuted at the Tribeca Film Festival earlier this year.

He has also lent his voice to the animated character of Dennis the Dog in Absolutely Anything, an upcoming live-action British comedy starring Simon Pegg and Kate Beckinsale, due out next year.

Fox was also in the middle of writing a sequel to 1993’s Mrs Doubtfire in which Williams played beloved Scottish nanny Euphegenia Doubtfire. While the project was in its early stages, Williams was on board. Director Christopher Columbus released the following statement after his friend’s death:

“We have lost one of our most inspired and gifted comic minds, as well as one of this generation’s greatest actors. To watch Robin work, was a magical and special privilege. His performances were unlike anything any of us had ever seen, they came from some spiritual and otherworldly place. He truly was one of the few people who deserved the title of ‘genius.’ We were friends for 21 years. Our children grew up together, he inspired us to spend our lives in San Francisco and I loved him like a brother. The world was a better place with Robin in it. And his beautiful legacy will live on forever.”

Fox issued this statement: “There really are no words to describe the loss of Robin Williams. He was immensely talented, a cherished member of our community, and part of the Fox family. Our hearts go out to his family, friends and fans. He will be deeply missed.”

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