i bought some ducklings September 14th from Metzer, to keep my one Cayuga duck company. Didn't know about the issues with crested ducks, so ordered four, along with some others. One of the White Crested was smaller than the others and a little shaky upon arrival. But she ate and drank and the shakiness stopped. But as they got older, she was still significantly smaller than the rest. Then a week or two ago, i noticed her crest was kind of off to the side. Now at six weeks, her neck is crooked and her whole head is off to the side. She doesn't have good balance. i've found her on occasion struggling on her back trying to get up. And the past few days i notice she doesn't get in the kiddie pool. Not sure if she can't figure out how to get in. i'm sure i've seen her in there in the past. But this crooked neck thing is new and might be making her balance off more than usual. i feed them Mazuri Waterfowl Maintenance, supplemented with pea, romaine lettuce, hard boiled eggs and occasional corn. i've read about them possibly needing added niacin and wondering if i need to add this to everyone's diet or just the little crooked neck one. i'm worried that she isn't getting in the pond, as she looks a bit dirty tonight. Perghaps i need to bring her inside tomorrow and wash her off in the sink. Any advice from the veteran duck folk on this board would be greatly appreciated.