H/t to @msbellows for pointing this out.

Do NOT give your babies or young kids aspirin for pain/fever unless directed to do so by your doctor. There is a life-threatening reaction called Reyes Syndrome that can occur with salicylates like aspirin when used in younger children.

Acetaminophen (Tylenol) is safe for most children at typically recommended doses. Ibuprofen generally is as well.