More pics in comments. Not sure if my LB has HFM / chicken pox?! He has a rash all over both legs, arms, face and hands. Pics attached are of specific blisters.
I’d say HFM too. It can be on their arms and legs as well as inside their mouth and genitals. Calamine cream, oat baths and calpol worked wonders for my little girl when she had it.
I think hand foot and mouth