It's even tougher when it's family.
Growing up playing my Dad (who is a great player) I usually lost all the time.
Then I got a little more interested and we started going back and forth on wins/loss
and now I am even better and add that he is getting older it's hardly a contest.
but He still enjoys playing but would often get upset at always losing.
so now we just Hit...do some drills maybe a mini game that gives him advantage...like he plays doubles lines and I get no second serve etc..