Something I really really liked about a few of the Homer/Lisa episodes in the earlier seasons of the show was how it paints a really sweet yet unconventional father/daughter relationship, basically in the way that Homer is a parental force to Lisa, so too is Lisa a parental force to Homer.
It’s really highlighted in one particular scene in the “future” episode “Lisa’s Wedding”, where Homer has a nice conversation with her just before her wedding.
Homer: Little Lisa, Lisa Simpson. You know, I always felt you were the best thing my name ever got attached to. Since the time you learned to pin your own diapers, you've been smarter than me.
Lisa: Oh, Dad --
Homer: No, no, let me finish. I just want you to know I've always been proud of you. You're my greatest accomplishment and you did it all yourself. You helped me understand my own wife better and taught me to be a better person, but you're also my daughter, and I don't think anybody could have had a better daughter than you--
Lisa: Dad, you're babbling.
Homer: See? You're still helping me.