Ideas?

I got 4 chicks on Friday. They’ve all been doing really well until yesterday. We have one chick that’s been dealing with pasty butt that we’ve been gently helping her with. I noticed that today she wasn’t coming out from under the heat plate all day. I figured I just wasn’t looking when she came out. After still not seeing her come out after I got off work, I gently pulled her out to look at her and her one legs is completely red, she doesn’t want to put any weight on in, I’ve moved the food closer to her so she can eat without moving to much and I’m taking her to the water. I haven’t been able to find anything online that even resembles what she has going on. She has no cuts, her leg looks fine other than being red. I don’t know for sure that she didn’t have this already when I picked them up (that’s my fault, I’m a new chick owner). Ideas? I’d like to help her as much as I can. This picture was earlier today. Earlier it was just her foot that was red and now it’s her entire leg.

I got 4 chicks on Friday. They’ve all been doing really well until yesterday. We have one chick that’s been dealing with pasty butt that we’ve been gently helping her with. I noticed that today she wasn’t coming out from under the heat plate all day. I figured I just wasn’t looking when she came out. After still not seeing her come out after I got off work, I gently pulled her out to look at her and her one legs is completely red, she doesn’t want to put any weight on in, I’ve moved the food closer to her so she can eat without moving to much and I’m taking her to the water. I haven’t been able to find anything online that even resembles what she has going on. She has no cuts, her leg looks fine other than being red. I don’t know for sure that she didn’t have this already when I picked them up (that’s my fault, I’m a new chick owner). Ideas? I’d like to help her as much as I can. This picture was earlier today. Earlier it was just her foot that was red and now it’s her entire leg.