Boy is that vague. But okay, useless little me tries to help. Have you searched the DT? It offers this:
PRETTY LITTLE BIRD
If I was a pretty little bird, I would never build my nest on the ground; I would build my nest in the highest oak tree* Where the wild boys couldn't tear it down.
And also ones named "The cuckoo is a pretty bird", "The dove she is a pretty bird", and lots of charming things about fair maids and birds and doting swains. Could you give us more information? Singer? Author? Traditional? Style? If you do I'll almost guarentee you'll find whatever you're after.
-J