Ouch...I so feel for your kiddos...I, being of fair Irish skin, blistered myself in the sun at the age of ten, of course back then (when dinosaurs still roamed the earth) there was not much relief for it, & to make matters worse we were having a family reunion/vacation in rural Kentucky at the time, & the burn pretty much ruined my good time & everybody else's as well...the only relief I got at all was from Solorcaine spray (a topical anesthetic that I'm not sure is even available anymore), the lotion hurt too much to apply, & sitting in front of a fan (no a/c available in that cabin) ...many years later, my #1 son would repeat my blunder, he was swimming at a friend's house & I wasn't there to monitor his sun exposure, & he had raised blisters much like you describe...as I recall, time was the only cure for his misery...

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