Why does this happen?

[tazmo]

Dd2 fell asleep in the afternoon and we realised she had a temp of 39oc. She had Calpol the ibuprofen later. Asked if she felt ok. Yep - fine! Today. No temp. No ill effects. Seems fine. Ds1 due to go swimming. If I take him, will have to take dd2 and dd3 in. I don't think she's ill now. Should we go swimming or not given the fact her temp was so high yesterday. Is something brewing? T

I would unless she has a history of ear infections.
If that was ds he would have an ear infection brewing and would probably be needing antibiotics within 24 hours or else his drum would burst. So I wouldn't take him.
I would take the other two, particularly dd2 who did run a high temperature for long enough to be sent home from school, have calpol/ibruprofen and be totally well again within 2 hours.