Hi, I had 5 ducks ages 8-14 weeks old. The youngest started acting funny 2 days ago. She started constantly squeaking instead of quacking and she stood hunched up by the fence instead of splashing in the pool with the others. Yesterday I found her dead on her side when I let the ducks out of the coop. Today one of my males has started squeaking loudly instead of his regurlar voice. I'm worried the same might happen to him. What could possibly be going on with them? They are all eating and drinking just fine.