Hello! I recently got three 1 week old baby Muscovies. Made my own indoor brooder in a large metal tub lined with plastic and covered in fine straw, and with a heat lamp above. Recently changed the straw to a peat moss/coco grow mixture. The first night they were home, one of them died. She was the smallest one, and was acting lethargic and eventually falling over and convulsing and would not eat or drink even with a dropper. This was a week ago. I have them on duck starter mixed with water, as well as a separate waterer which i add greens to throughout the day. It has been a week, making them 2 weeks old now and the other two have been very active and healthy seeming with bright personalities, both eating voraciously. I have been taking them to forage around the yard and woods and for a swim in a baby pool about twice a day. I am beginning to notice now, however that one duckling is MUCH larger than the other one. close to twice as big i would say. The smaller one is very "puffy" is the only word I can think of. Its very hard for me to tell if she just seems puffy because shes much smaller, but when i feel the larger ones back i can feel his muscles and he seems much more lean and long, while the small one seems round and fat. (I am calling the large one a he and the small one a she because I feel like that is their genders since muscovies have massive size differences between sexes?? But not sure about at 2 weeks already???) Like I said they are both active, and if I had to guess based on personality they are both healthy. However, the puffiness has got me worrying, and today when I was feeling the small ones back i noticed that just at the base of her back there was a spot that when I stroked it she would twitch a little bit, or seem uncomfortable. I pushed the feathers aside and the skin is very red in that spot. I almost thought she was bleeding, but its just very red. Her legs also seem far apart but I cant tell if its just because she is so round. She looks like a tiny round little puff ball while the other one looks more "duck-shaped" if that makes any sense. Is this something I should be worried about at two weeks? Also the first time I changed the bedding after two days I noticed some mold at the bottom. I guess I need to change it every day? Please any info would really help, I'm very worried and scared of losing another one...the two seem to just love eachother!! The little ones poop also seemed watery but I guess both of theirs can be different throughout the day... So to recap: -Is it normal at two weeks for their to be such a vast size difference between two ducklings from the same brood? -Is their any explanation for why one would be very round and "puffy" while the other is lean and long? -Do ducklings usually act sick when something is going wrong or will they continue to be extremely active and eat well through some problems? -What could the very red skin patch mean? Thanks so much for your input! Could try to post photos too if anyone thinks that might help. NOTE: the ducks in my profile picture are NOT the ones I'm talking about, those were the scovies I had two years ago at 4 weeks old, just to spare anyone the confusion!!