Demi Lovato, Helena Christensen and Aaron Paul are among the stars to send support to Bruce Willis' family after they revealed the actor has been diagnosed with dementia.

Bruce Willis has dementia

Bruce Willis has dementia

The 'Die Hard' actor retired last year after being diagnosed with aphasia but now his loved ones - wife Emma Heming and their kids Mabel, 10, and eight-year-old Evelyn, and former spouse Demi Moore and their daughters Rumer, 34, Scout, 31, and 29-year-old Tallulah - have announced his condition has "progressed" and he has been given a "more specific" diagnosis of frontotemporal dementia (FTD).

In response to their joint statement, a number of their famous friends have offered love and support.

Lovato commented on the 'Ghost' actress' Instagram post: "Sending so much love.. [prayer and heart emoji]"

And supermodel-turned-photographer Helena wrote: "Sending you so much love, it is so wonderful you’re such a tight knit family, it makes all the difference."

She also wrote on Scout's post: "Sending you love and strength to go through this together [heart emojis] (sic)"

Meanwhile, Aaron hailed the 67-year-old actor a "damn legend" in his comment on Rumer's Instagram account.

He wrote: "Love you so much my friend! [heart emoji] Sending hugs to you and that beautiful family of yours. Your pops is such a damn legend."

Marlon Wayons wrote on Demi's account: "Love to you, him and the family. You're an amazing human. It's beautiful to honor him and your family the way you are. Makes my heart smile."

Ireland Baldwin also posted on Rumer's announcement.

She posted: "Sending you and your family all my love, always."

Selma Blair, Sharna Burgess, Liv Tyler, Busy Phillips, Naomi Campbell and Sophia Bush all declared they were "sending love", while others, such as Melanie Griffith and Olivia Munn simply left heart emojis in the comments as a show of support.

CNN anchor Jake Tapper revealed he had personal experience of the "profoundly cruel" disease.

He tweeted: "FTD is a profoundly cruel disease, my beloved father in law Tom suffered from it for years before he died. Sending all my love and prayers to their family."

Maria Shriver praised Bruce's loved ones for speaking out.

She tweeted: "My heart goes out to Bruce Willis and his family, + also my gratitude for shining a much needed light on this disease.

"When people step forward it helps all of us. When people get a diagnosis it's extremely difficult, but also for most a relief to get a diagnosis."