Psycho or leave it

Hi guys so I just found out my recent ex, baby daddy hasn’t even told his father I’m pregnant. I have 9 weeks left. Due date is January 2nd. He told me he told him. Sooo my question is should I go to his dads house and invite him to his granddaughters baby shower and tell him he’s going to be a grandpa.

Or should I leave it and let his family be out of the loop until he gets the balls to tell them.