Bruce Willis sings and blows out candles as he celebrates 68th ...

Bruce Willis has celebrated his 68th birthday with a song and a cake, surrounded by his family, after it was announced he had been diagnosed with frontotemporal dementia (FTD) earlier this year.

A video shared by his ex-wife Demi Moore showed the Hollywood star singing happy birthday while surrounded by his daughters, Moore and his wife Emma Heming, before blowing out two candles on an apple pie.

Relatives of the Hollywood star said in March 2022 that he would be "stepping away" from his successful career after being diagnosed with aphasia, a condition affecting his cognitive abilities.

Moore, 60, wrote alongside the Instagram post: "Happy birthday, BW! So glad we could celebrate you today. Love you and love our family.

"Thank you to everyone for the love and warm wishes - we all feel them."

Heming, 44, also shared an emotional post on Instagram, describing the feelings of "sadness" and "grief" she said she experienced as a caregiver to someone with dementia, adding: "I'm really feeling it today on his birthday."

Becoming tearful as she ended the short video, she thanked fans for their support, saying: "As much as I do it for myself, I do it for you because I know how much you love my husband."

Starring in more than 100 films over four decades, Willis has appeared in box office hits including Pulp Fiction, 12 Monkeys and The Sixth Sense, earning him fans worldwide.

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Hemming also shared a collection of videos and photos of Willis spending time with his family and playing with his children.

She captioned the post: "He is pure love. He is so loved. And I'll be loving him always. Happy Birthday my sweet.

"My birthday wish for Bruce is that you continue to keep him in your prayers and highest vibrations because his sensitive Pisces soul will feel it.

"Thank you so much for loving and caring for him too."

Willis has five daughters, sharing his three eldest - Rumer, Scout and Tallulah - with Moore whom he married in 1987, and his younger daughters Mabel and Evelyn with Hemming, who he married in 2009.

Willis and Moore separated in 2000, but remain on good terms.

Rumer marked her father's birthday by posting the same video of everyone singing happy birthday and wrote: "Happy Birthday Daddio I love you to the moon. You are so cool."

Scout captioned the video in her post: "Also though, today has been PROFOUNDLY JOYFULLLLLLLLLLLLLLLLL !!!!!! HAPPY BW'S BIRTHDAY TO ALL WHO CELEBRATE !!!!"

Tallulah shared a selection of photos of her father from throughout the years on her Instagram, writing: "Happy birthday to my numero uno Bruno !!

"Feeling awash with all the good energies and love headed this Willis way! I love him and he loves me - what a delight!"

FTD is a degenerative brain disorder characterized by deterioration of the frontal and/or temporal lobes, according to the Association of Frontotemporal Deterioration (AFTD).

They list symptoms including uncharacteristic personality changes, apathy, and unexplained struggles with decision-making, speaking or language comprehension are among the most common presenting symptoms.

There are currently no treatments for FTD.