*My practical advice* simply tell them that HP is the most popular movie and book series of all time, and tell them to stop calmy.
*My preferred advice* YEET THE CHILD
honestly teachers just go like
"dOnt dO iT aGaiN aND iF i eVer hEar aNYmoRE cOmpLainTs thEre wiLL bE trOUbLE"
but then people are still toxic and the teacher doesnt do anything