The documentary "Susan" follows a woman living with frontotemporal dementia and her advocacy for others with the disease, highlighting the emotional impact on her family and their efforts to continue her legacy.

Peter Alexander was 49-years-old when he was diagnosed with dementia, or more specifically frontotemporal dementia (FTD) - the same condition that both Bruce Willis and Wendy Williams have developed in recent years.

In an Instagram video posted by his wife Emma Heming Willis on Thursday, Willis is seen interacting with Los Angeles police officers, shaking hands and posing for a photo.

Peter Alexander was diagnosed with frontotemporal dementia seven years ago and has issued a warning after spotting small sign of the disease.

Actor Bruce Willis, 69, has been photographed on an outing in Studio City, Los Angeles in a rare public appearance following his dementia diagnosis