Maybe you can take turns attending sporting events. Even in intact family where both parents live together, they often take turns attending events. People work night shifts, wotk long hours, attend school, take care of elderly relatives etc Unless both people have no other obligations and are independently wealthy and don’t have to work, they can’t always both attend all events.

I think it’s healthy for dad attend one event alone and try to bond with his kids. He doesn’t sound very involved Doesn’t talk to them directly? Only through you?)

. Give him opportunity to be there for his son while you perhaps take a break