Help! What's wrong?

[pfd]

My baby Keyster all of a sudden has this strange swelling (it's hard). What is this and what can I do? It seems that he/she doesn't drink much either.

 

[ivan3]

Perfectly normal: http://en.wikipedia.org/wiki/Caruncle_(bird_anatomy)

Just make sure there is plenty of fresh water available, they like to stand in it as well as drink it.