Actress Dame Barbara Windsor, best known for her roles in EastEnders and the Carry On films, has died aged 83.
Her husband Scott Mitchell said she had died peacefully from Alzheimer's at a London care home on Thursday evening.
He said she would be remembered for the "love, fun, friendship and brightness she brought to all our lives".
The Prince of Wales and the Duchess of Cornwall, who both met Dame Barbara, paid tribute to her acting and charity work.
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Prime Minister Boris Johnson added: "So sad about Barbara Windsor, so much more than a great pub landlady and Carry On star."
He added that she was "one of those people that just cheered you up, and cheered everybody up because she had a kind of irrepressible naughtiness that was totally innocent.
"She did a lot of good work for charity and looking after lonely and vulnerable people, she lit up people's faces."
Sir Elton John added: "The world has lost the biggest ray of light. And heaven has the sweetest and funniest angel."
The BBC's EastEnders programme also paid tribute, saying they were "all deeply saddened".
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Dame Barbara was diagnosed with Alzheimer's in 2014 and had moved to a care home earlier this year.
She appeared in nine films in the Carry On comedy series, plus Sparrows Can't Sing, for which she was nominated for a Bafta, as well as parts in Chitty Chitty Bang Bang and On the Fiddle with Sir Sean Connery.
She was well-known to millions of TV viewers for her portrayal of landlady Peggy Mitchell in EastEnders, starring alongside her on-screen children Ross Kemp and Steve McFadden.
Her last appearance in the soap came in 2016, the same year she was made a dame for her services to charity and entertainment.
She also worked in theatre - making her stage debut at 13 - and appeared in productions including Oh! What A Lovely War and Fings Ain't Wot They Used To Be.
Dame Barbara's 'ripple of warmth'
The moment you met her, she had an ability to make you feel like an old friend. She was funny, warm and engagingly open, she would arrive in a room and bring with her a little ripple of warmth.
And the character you saw on TV and film was remarkably close to the person you would chat to before and after an interview. She was from a generation of working-class actors who had got their break in the 60s when theatre directors like Joan Littlewood were looking for talent that seemed real and natural on stage and screen.
That's not to say she wasn't also tough and canny enough to know how to turn on the charm. Her life was a story filled with gangsters, set backs and determination to succeed.
She had decided to act when she was a child and there was behind the laughter the sort of steel you need to have a career that lasts nearly 70 years. There was a definitely something of her character in the tough EastEnders landlady, Peggy Mitchell.
But she was always open about her ups and downs, she didn't hide the flaws and vulnerabilities, which only made her all the more likeable.
After her dementia diagnosis, Dame Barbara became an ambassador for the Alzheimer's Society and met Mr Johnson to raise awareness about the disease.
The star delivered a letter signed by 100,000 people pleading for better care for people affected by dementia and saying the system was "completely inadequate, unfair, unsustainable and in dire need of more money".
Mr Mitchell, who campaigned alongside his wife, said of her death: "It was not the ending that Barbara or anyone else living with this very cruel disease deserve.
"I will always be immensely proud of Barbara's courage, dignity and generosity dealing with her own illness and still trying to help others by raising awareness for as long as she could."
The couple went public with her diagnosis in 2018 and Mr Mitchell had said they had been "really nervous" about revealing she was affected by the condition.
In his statement he thanked the public, family and friends for support which he said "Barbara deeply appreciated".
He added: "I've lost my wife, my best friend and soul mate and my heart or life will never feel the same without you."
The Alzheimer's Society said it was "incredibly grateful" to Dame Barbara and her husband for their work bringing awareness to the disease.
In a statement, the charity said: "Dame Barbara Windsor was an amazingly true, much-loved national treasure, and in speaking out about her experiences shone like a beacon for others affected by dementia."
Like her EastEnders character, Dame Barbara was born in east London, in Shoreditch in 1937.
The actress married Mr Mitchell in 2000, with the pair having first met in 1992.
If you, or someone you know, has been affected by dementia you can find more information and support here.
Did you meet or work with Barbara Windsor? Or has her Alzheimer's disease campaigning helped your family? Share your memories and experiences by emailing firstname.lastname@example.org.
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