That's just like a girl—they're so thin-skinned and chicken-hearted.
Say, you're not losing your nerve, you chicken-hearted rabbit, are you?
Why, they turned out to be kind of chicken-hearted after all.
He is too chicken-hearted for that, or for anything else that requires pluck.
What a chicken-hearted fellow her father must have thought me!
They are chicken-hearted ...