Translation of "Kindereien" in English

I was far too old and too big for such childish things.

Until now, I only did stupid, childish things.

Still, those were childish pranks!

You don't have to resort to such childish pranks.

Are you almost done acting like a child?

What do you care about children's stuff?

Reading? You won't have time for that sort of childishness now, Anna.

I've had enough of your childish behaviour.

But that is nonsense, comrades.

All words seem childish to it.

That's something strange: all human qualities and faults look like childishness-foolishness.

That is nonsense, comrades.

Our relationship is of such a nature that it cannot be altered by such childishness.

Or... because you're annoyed because you think I like Dylan better than you or some childish nonsense that's in your head. Oh, so it's all about you.

Come down here compromising my cover, and now you're gonna ask me to risk my whole career over this nonsense?

This is childish.