Board Thread:Theories and Rumors/@comment-26509603-20150619132817/@comment-26509603-20150809122757

Mr.reporter wrote: I pretty sure that Wu said it is because of paternal to son and maternal to daughter.

When? If you're talking about when he said to Nya something like, "As Kai took on the elemental traits of your father, you must take those on of your mother, as the Elemental Master of Water," then that's not really him saying that elements passing down is paternal or maternal. He was just stating that since Kai took on the element of her father, she would have to take on the element of her mother.