When is this theme ever going to die? Confirmed bachelor(ette)'s life gets turned upside down by the sudden addition of precocious 7 year-old child who teaches about love and responsibility.
This theme dates back to the days of Shirley Temple, and probably even further than that. I personally don't know any single person who's life was changed for the better with the sudden responsibility of taking care of child. Seriously. None.
If those kids wound up on my doorstep, I would farm them out faster than you can say "Santa Claus ain't real," and go back to watching TV in my underwear.
I'm just saying.