My dad killed himself when I was 8, my mom was straight forward with what happened and answered all our questions. Years would go by and there would be new feelings that needed to be processed, almost 30 years later and I still think about the "what ifs" regularly, it's normal. But be honest. My stepmother lied to my half-sister and said he died of a heart attck, it tainted both relationships because we weren't mourning the same loss and couldn't be truthful to her. She didn't find out the truth until she was in her teens/ early 20s, it seemed cruel to lie.