三つ子の魂百まで
1
a leopard cannot change its spots;the child is father to the man;the soul of a child of three (is the same) at 100
三つ子の魂百までとは本当によく言ったものだ。
'The child is father to the man' is certainly well said.
Other forms
三つ子の魂百迄 【みつごのたましいひゃくまで】 (search-only kanji form)