Anyone now what this is?

No one here is qualified to say. Take her to the doc.

Looks like hives..maybe an allergy rash

I wouldn't like to say but I'd just let the dr have a quick look to put your mind at rest. It doesn't look anything serious, just irritating.

It’s hard to say, but it could be hives, which you get from an allergic reaction. Is she taking any medicine, or had a vaccine recently? I got them from a certain antibiotic and once when I ate strawberries. It’s what looks like a raised welt in the middle of the red area. They are itchy. See the doctor because allergic reactions can turn serious.

I know you're looking for a quick hand, but this is your child. She depends on you to keep her healthy and free of distress. Additionally, rashes can be outrageously contagious. Get her to the pediatrician; I'm sure it's nothing a simply ointment or cream can't help, but only a physician can guarantee that.

Could be hives or eczema.

Could be the start of exema as was said doctors is your next stop

She could be having an allergic reaction to something.

Benadryl cream...if that doesnt work take her to the doctor.

Probably an allergic reaction to something

Chicken pox maybe

See a Doctor buuut my daughter got these hive looking things often. Super sensitive to everything when she was little.

If it’s safe try some Benadryl for the night but for sure see a Doctor.

did you change or add any new foods or lotions-soaps ( even laundry soaps) ??

Looks like an allergic rash. Take her to the doctor just to make sure.

Talk to a pediatrician, trolling for best guesses here is insane

She'll be fine