I purchased two mille fleur d'uccles in June from a breeder in the Northwest. A couple of weeks ago one of the birds all of a sudden developed a bum leg and can no longer use it. Her foot has no sensation but there is no necrosis. She gets around by hopping on her good leg and resting often. Now, her sister is suddenly displaying symptoms similar in nature. I'm away for college, but I got a call that Sadie was walking like her knees didn't want to work correctly. She's walking with her chest almost on the ground, bent over. I'm worried that she will soon be unable to walk at all. Any idea what it could be? As far as I know there are no other symptoms.