Since she was a baby my DD has head butted her mattress when in bed and about to go to sleep. As she has got older it continued mostly when anxious/she can’t sleep. Since lockdown this stopped (yea!) as no school and less stress. However this morning she got up sporting a big (2inch) bald patch on her hairline right in the middle. She eventually admitted that she’d not been able to sleep and had rubbed her head on the headboard of the (new) bed we’d got her. Make me feel better by telling me how quickly it will grow back. There’s an obvious bald hole.