What is this rash? (Photo)

[Freco010]

My 4yo has developed these spots on her neck and back. It seems to come and go. There isn’t a lump and it doesn’t appear to be bites. It’s very itchy.

Looks like it could be hives. Has she been unwell recently or anything she might be reacting to?

I wondered hives. She hasn’t been unwell, but has been anxious since starting school. Could it be caused by anxiety?