It's the most wonderful time of the year to dig up childhood resentments! One thing almost every human being has in common is that we are all at least a little bit screwed up by something our parent(s) or guardians did (or didn't do). And no one knows more about the things our parents did wrong than therapists. Parenting mistakes are their bread-and-butter.
(Read with caution, cookies, and Kleenex on hand as these answers may be triggering if you have imperfect parents, which most of us do.)
1.) From Chubuwee:
Behavioral therapist here. Catch your kids being good!
Parents are always telling kids what they did wrong. You have to balance it out by telling them what they are doing right.
2.) From Polyfuckery: