Any idea what this rash is?

[Gdir53]

Started with just a few pimples but seems to be spreading on one side of DD's back/neck. It is starting to spread to the front along the collar bone line. Just a few onthe other side. She doesn't seem too bothered by them.

Not really bad enough to ask a medical opinion so asking on here!

Thanks!

Hard to tell from the picture but maybe the pictures on here will be useful x

https://www.nhs.uk/conditions/rashes-babies-and-children/

Any of them have a blister on top? In my experience, chicken pox tends to start on the upper body/neck area.