Picked my 21m old son up from daycare today, he was outside playing which they have been doing a lot now that the weather is nicer. It was about 75 degrees out and overcast. He was beat red - face, neck, ears, scalp, arms... my immediate thought was sunburn but his teacher (whom I really respect and trust) said it was a little raised and she thought it was prickly heat. Had to look it up - just another term for heat rash. So we can home and hung out inside where it was cooler - the redness went away mostly but still visible on his ears and neck. He’s been drinking water all afternoon - no more or less than usual. After dinner (he didn’t eat much) he had some pretty nasty diarrhea, we gave him a bath, and a diaper rash had developed. He never has diaper rash 😕 and we noticed a blister on his buttcheek/thigh area. Sorry, no pics. Does it sound like prickly heat? Possibly dehydration? Anything else? I’m hesitant to call the Dr because he’s acting normally - not cranky, no itching.