When child is sixteen years old he can do as he likes, not before that.

lalayet panca varsani
dasa varsani tadayet
prapte tu sodase varse
putram mitravad acaret

This is the moral instruction of Canakya Pandita. Up to five years, don't chastise, don't take any action. Let him be free. Whatever he likes, he can do. Then after fifth year, for ten years you must be very strict. Then five years and ten years, fifteen. And when he is sixteen years, treat him like a friend. Prapte tu sodase varse putram mitravad acaret. At that time, no stricture that he will break. "My dear boy, if you do this…" This is necessary. And from fifth year to fifteenth year you should chastise the sons and disciples just like tiger. After five years.

Srila Prabhupada, April 5, 1977, Bombay