This is my own speculation, it’s not based on any statements from the creative team or actors or anything. But I noticed a few things, and the presence of Ed O’Neill playing the family patriarch on both shows helped.
The cast is the big giveaway. In Married With Children, we’ve got a family consisting of Al and Peg Bundy, and their children Bud and Kelly. The marriage is rocky, they don’t get along well. Al constantly dreams of finding a hot wife to replace Peg. It’s worth noting, though, that when the shit hits the fan, Al is loyal to his family. Hmm… Crazy ex wife, hot and nice current wife, loyal to his family, and played football in High School? Sounds like Modern Family’s Jay Pritchett. Seems you can do well for yourself once you don’t have a crazy person sucking up most of your income.
The kids? Bud Bundy was bad with women, but constantly seeming to work himself into a parody of hypermasculinity. While far from universal, or necessarily even common, some people do this to hide being gay. Bud, if he was such a gay man, once he learned to accept himself could have turned out much like Mitchell Pritchett of Modern Family.
Kelly was a dumb, promiscuous blonde. On Modern Family, we’ve got Claire Dunphy(neé Pritchett), who is blonde and was implied to have gotten around a bit during high school in an episode where she met up with an old friend. While Claire shows much greater mental capabilities than Kelly typically did, several episodes of Married With Children implied that Kelly was, fundamentally, brilliant. She never used or developed her intellect, but it was there. With the right motivation, she could easily become as intelligent as Claire.
Fanfic writers, I expect the thrilling tale of the Bundys busting up a meth ring and going into witness protection.
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