If the son gets sick like that again, use a doctor's consultation on him, he might have an infection.
Actually, he had the hiccups, then a headache, then a stomach ache, then a rash... all things that I cured, but they left him extremely weak. I did do a doctor's consult anyways, but it said that he was healthy (which he was at that point) even though he was extremely weak.
I'll have to keep my fingers crossed for the adoption event... this was the first family I started, and I've got all the upgrades (rooms and house), lots of trophies, and many collectibles. I don't want to have to start all over again, lol!