Our 4 month old frizzle does not seem well. When we got her a month ago, she seemed a little clumsy, but now seems worse. We've checked her legs and feet, and nothing noticeable. She can hobble along, doesn't seem as though right or left leg is obviously worse, but she often seems to lose her balance and fall over. She quickly rights herself and keeps going. She also is sitting down a lot. She is eating and drinking, and seems to have energy (she'll race around the run occasionally if another hen pecks at her). Our other birds we got at the same time and roughly the same age (but all from a different flock than her, oops, we didn't know about quarantine, we're new to this and I really wanted a frizzle!) all seem super healthy and are growing quickly. They don't pick on her specifically. I've been trying to determine what seems weird about her walk. Maybe her legs from the knees down (are those knees??) seem to angle forward more than the other birds, which seem to have straighter lower legs, situated right under their body. Anyways, I've been doing lots of online research to try and figure out what it may be. I'm REALLY hoping it's not Marecks, but doesn't seem to affect her wings (though she's never really tried flying so hard to say) and haven't noticed anything weird about her eyes. What about rickets? She is too young to be laying, so she's not losing calcium to eggs. We feed them a layer feed, and toss in some veggie scraps and salmon skin when we have some. We also toss them slugs from the garden. They have a covered run that is not in direct sun, but it seems crazy that the frizzle would have a severe Vit D deficiency and the others would be fine. Any ideas, or ways to further diagnose her? Thanks! She's a pretty loveable little runt.