What kind of parent sends their kid to school with a fever ?

I mean it could be the fact that they don't know, the kid might not show symptoms until they reach school and they feel sick go to the nurse's office and have their temp taken. Same thing with the stomach bug, When I was in middle school around December I went to school but apparently I had the stomach flu because Later on during the school day I fell sick and I while waiting for my mom to come I threw up a lot. I didn't go back the next day