Board Thread:Theories and Rumors/@comment-34367497-20180710063048/@comment-26921673-20180711210219

She is probably some random Oni girl from the First Realm that the FSM fell head over heels for. Being the mother of the first Spinjitzu master is pretty unlikely as that would mean she's way older than the FSM and somehow hasn't died yet. Also, I don't think the FSM really had parents...

He might've just appeared out of no where as a hybrid of the two races' powers.

in episode 89, we found out that he "bonded" with Firstbourne as he had dragon blood. I find it strange that he'd bond with a different dragon then his dragon mother/father, so I don't think he has parents.