Dummkopf Trumpf's niece, the clinical psychologist and bestselling author Mary Trump, sees "similarities" between her uncle's (79) increasingly erratic behavior and that of his father, the NYC property magnate Fred Trump, who suffered from Alzheimer's before dying in 1999 at the age of 93. "I think the most important thing to know about Donald's health is that this is a person who has had very serious, severe psychiatric disorders that have gone undiagnosed and they have worsened because they've never been treated," Mary Trump said. "So much of what we're seeing is the result of those undiagnosed, untreated psychiatric disorders. On top of that ... there are clearly some physical health issues, and often it seems that ... it's not just that he's forgetting things. He doesn't seem to be oriented to space and time or place and time. I see it in his eyes."