The Nice Guys has an assassin nicknamed "John Boy" for some Celebrity Resemblance, highlighted by a character as "Um... Holly, what's the name of the guy on The Waltons that plays John Boy? With the hockey puck on his face?".
The Dresden Files: In Ghost Story when told that they're like family, Fitz snarks that their gang is like The Simpsons. Harry opines he would've opted for The Waltons.
7th Heaven: In "The Color of God," when Lucy, Mary, and Keesha say "goodnight" to each other before going to bed, Lucy remarks that it feels just like being on The Waltons, except the Waltons weren't...
Lucy: Hey, this is just like being on The Waltons. Except the Waltons weren't-
Mary & Keesha: (in unison) Black, we know.
The Love Boat: In "Daddy's Pride," a man says that his gymnast daughter will someday make Nadia Comăneci look like Grandma Walton.
Animaniacs: One of the closing gags depicted the Warners saying goodnight to each other a la the Waltons closing credits. A variant of this gag actually has them saying goodnight to John Boy.
"LET ME OUT OF THIS TOWER!"
Family Guy: In "PTV", one of the shows airing on PTV is an episode of The Waltons in which the "Goodnight" ending plays out until John Boy doesn't respond. When Olivia walks into his room, he yells "Dammit! Can't a guy masturbate in this house?!"
The Simpsons: George H. W. Bush famously criticized the show in a speech about family values by negatively comparing the Simpsons to the Waltons. This was referenced in a special Cold Open for a rerun of "Stark Raving Dad", in which the Simpsons watch that very speech on TV.
Bart: Hey, we're just like the Waltons! We're praying for an end to the depression, too.
