One of our senior partners had a child that once stood up on a seat and loudly demanded an explanation why a regional J seat didn’t go flat, as the passengers in economy were passing through on their way to the back...
Not loudly but I clearly remember my daughter (now 10) once sitting down in a WT seat when she was about 4 or 5, and asking me why the seat won't go flat...
It was at that point I realised she's way too spoilt, and the occasions we've taken her in anything above WT/WTP since are few and far between (of course the fact that we now have 3 of them to pay for also has something to do with it...).