Bruce Willis has been diagnosed with frontotemporal dementia, his family has announced.Relatives of the Hollywood star, 67, had previously said he would be "stepping away" from his career after being diagnosed with aphasia, a condition affecting his cognitive abilities. His daughter Rumer has now confirmed Willis's condition has "progressed" and he has been given the more specific diagnosis of frontotemporal dementia."Unfortunately, challenges with communication are just one symptom of the disease Bruce faces," a family statement read. "While this is painful, it is a relief to finally have a clear diagnosis."