It's interesting that you mention this. He had a very difficult father, and a difficult relation with him. Obviously he overcame that hurdle and became quite successful. However, his half-brother, 15 years his junior, who also successfully wrote for a living (as a journalist), apparently suffered a lot more from it.
Source: he was a family acquaintance, and it's mostly public knowledge on Wikipedia. Since both brothers have passed away now, I believe it's reasonable to write this.