I recently acquired 4 ducklings from tsc, 2 pekin and 2 rouens. The 2 little pekins were both a little weak from being shipped and I lost one the first night. I could tell for sure that one was sick but the other one seemed just fine really running around with the others. Now a week later we have noticed that one of them sits a lot. It doesn't appear to be in pain but it is like they cannot stand for long. It waddles around with the rest of the ducks but every time they all stop it sits down. When the rest of them decide to move on it gets up and walks right with them. When they stop it immediately sits down again. I cannot see anything wrong with it, the knees don't look weird or swollen, nor the feet, and it does not appear lethargic. It also eats and drinks as it should and loves treats.I have been putting electrolytes in their water and as of last night started sprinkling brewers yeast on the food. Am I just being overly paranoid as it is still a pretty young little thing or do you have any advice as I am a new duck mama (have 9 chickens though 
