Conversation so far:
Where was Sam Harris born?
Sam Harris was born in Los Angeles, California.
Who were Simon Harris' parents?
Sam Harris is the son of actor Berkeley Harris and TV producer Susan Harris.
Was Simon Harris raised in any particular religion?
Harris has stated that his upbringing was entirely secular and that his parents rarely discussed religion, though he also stated that he was not raised as an atheist.

Question: When did he decide he was an atheist?
Self-contained rewrite: When did Sam Harris decide he was an atheist?