Why is the life of Jesus when his younger years is not written in the Bible?
He was mentioned as a boy that marveled some people, in the bible, and after that his next mentioned was as a grown-up ready for his mission. Since it was not yet his time to preach because he was too young, he was at home preparing, doing carpentry, helping joseph. He was preparing for the mission. Because he will carry the cross. It was not written because his life then was a routine, and only important things are written about him.