I'm touched in my reading about Bowies' relationship with his schizophrenic brother, Terry Burns. It seems they were close in their younger years.
Terry introduced Bowie to modern jazz when he was growing up. Burns, who was Bowie's mother's son from a previous marriage, was severely schizophrenic. Burns killed himself in 1985 after escaping the grounds of the hospital and laying down on some railroad tracks.... He was 47.
Bowie wrote several songs about his brother's struggle with mental illness, including "All The Madmen" and "Jump They Say."
There had been a lot of mental illness on Bowie's mother's side so Bowie by 23, he felt the odds were possibly high of him going mad. This naturally terrified him and would be the catalyst for much of his excellent work in the 1970s. His songs dealing with identity, control, lunacy and fear; devising personae as various means of escape, as conduits for insanity.