Riot's parents were the focus of the episode, "Riot's Hope".
We learned of Riot's childhood and about his father HATING Riot's passion for music.

A military man, Riot's dad felt music was for girls, not men.
Riot's mom supported the love for music, and even taught Riot(Rory to his mom) how to play the piano.

Needless to say, after years of bickering, his mom got sick.

It was father and son making up that finally made her well and ended the feud.