There is a colorful cow hidden in every single episode of Nicky, Ricky, Dicky, and Dawn.
Allison Munn who plays Anne Harper was pregnant with her second child while filming the episodes.
Mace Coronel mutually "parted ways" with Nickelodeon and left the show in August 2017 before filming the final 5 episodes of the Season 4. He did not appear in the last five episodes.
Dawn was supposed to be male named Don and Nicky was supposed female named Nikki. The quads last names were supposed to be Hayley but the producers chose Harper instead.
Thomas Kuc auditioned for the role Ricky but lost the part to Casey Simpson. He ended up scoring a leading role as Hudson on the Nickelodeon sitcom Game Shakers a year later.