Too funny.

My kids have big heads too. DS6 as an infant/toddler was always 1.5 cm ABOVE the top of the chart! DD5 started out with a smaller head (being a preemie) but at 6 mos had rapid head growth and then stayed with the bigger than average head.

They certainly don't get it from me!!
DS could wear MY sunglasses before he was 2 and needed a 5+ bike helmet at 2.

The masks and hats for costumes have never fit him until this year - amazingly his Mario hat actually fits!!