Rash? 4 months any ideas?

[trampolinebouncer]

4 month old - has a tiny temp 37.5 but apart from that & the rash pictured happy & feeding/interacting normally.

Any clues on the rash? It is on the body front and back and legs around the knees.

He was inadvertently around Chicken Pox a few weeks ago - interacted with a child the day before his rash came out -

Could be prickly heat? Or google roseola

Do you know what LO's base (normal, resting) temp is? For mine that would be a temperature as she is a degree below that normally

@CellarFloor - not 100% sure of the base probably 36.7 - he feels a little bit warm - gave calpol last night & this morning rash still there but not appearing unwell.