I have four ducks about three months old, two Khaki Campbells and two Welsh Harlequins. One of the WHs is so passive and quiet that I have wondered if she's either sick or stupid. This morning I put a small pen around her pool just so she could eat mealworms without the other ducks getting to them first. She has always been the shyest duck, the one least likely to jump in the water or eat out of my hand. While three sleep together or hang out together, she is always off on her own. Sometimes I see her standing there with her eyes closed. The other ducks aren't mean to her, nobody's pecking at her. She has been withdrawn from the day I got her. Is this normal behavior for a duck?