babyish

It's not babyish to be afraid of scary things, Max told himself.

"Buy me a gun," Amir replies haltingly, his words jarring with his babyish voice.

“Our first song, because we were so touched by all of that music, came out in babyish, broken English.”

But unlike Lear she is a mother; Colin, though often rough and gross, is in Nick Holder’s wonderful portrayal surprisingly babyish and dainty underneath.

Ellie is supposed to be 14 but in both performance and writing she behaves like a much younger child, more immature, flippant and babyish than most 11-year-olds.