Prunes
(source: "The Worm Song and Other Tasty Tunes, Janet Wilson, 1993.)

No matter how young a prune may be

He's always full of wrinkles.

A baby prune is like his dad but he ain't wrinkled quite so bad.

We have wrinkles on our face

But a prune has wrinkles every place.

No matter how young a prune may be

He's always full of wrinkles