Brown-haired Aurora and red-haired Fargico's third child, Gepozo, ended up with black hair and a head that is much further up the chart than his parents' ones.
Redheads Brett and Mimi, after four sons who were also redheads, ended up with a brown-haired daughter (again, further up the head chart than them). Their son Theodore is blond, but he's adopted.
And Rowena really stands out among the blonde children of Moira and Inacio, who both have blonde hair as well. Rowena has purple hair but her head is among the brown-haired ones in the head chart.