Rivalry: A rival to you or your family cause upheaval forcing you to relocate possibly to a far distant land. (Work with your DM to detirmine the details)
Divorce: During your adolescence your parents split up and you were forced to chose which parent to live with (Work with your DM to detirmine the details)
The character is adopted into a Wealthy family. If he is an orphan, it is a true adoption. If he has living parents, he is treated just like a son. (work with your DM to determine details)