expression, godan verb (-tsu)
sleep brings up a child well; a well-slept child is a well-kept child
Proverb emphasizing that children who sleep well grow up healthy and well-adjusted.
「寝る子は育つ」と言うから、早く寝かせよう。
They say 'sleep brings up a child well,' so let's put him to bed early.
A traditional Japanese proverb. The exact origin is uncertain, but it reflects the long-held belief that sufficient sleep is essential for a child's healthy development.