I think it is a combination of external factors such as society, parenting, social environment, and of one's genetic disposition. We all have tendencies to certain behaviours and dormant genes that may or may not be activated depending on our environment.

Although some things may be up to chance I truly believe solid parenting (and now I don't mean "goodwilled" parenting because one might have good intentions but cause negative behaviour nonetheless) is the most important key for a good childhood.

Otherwise, if you're into travelling, vlogs, fitness, self-development etc feel free to check out my channel, in any case keep up the good work and I'll see you around! :)