ellenscoop
Songster
Take her to see a vet to help figure out what is causing it. Please don't attempt to drain it out yourself, it is a very risky procedure, that even highly trained avian vets that do it have birds that die from aspirating. Take her to see a vet. It is a serious issue. Here is a directory of vets who see chickens - http://www.poultrydvm.com/poultry-vets.php