Gary Valentine, originally Gary Joseph Knipfing from Mineola, New York, is the brother of actor Kevin James and has German roots. Beginning his career in stand-up comedy, Valentine soon gained traction in Los Angeles, making appearances on renowned talk shows like The Late Late Show with Craig Kilborn, Late Night with Conan O'Brien, and The Tonight Show with Jay Leno. He's notable for his nine-season role as "Cousin Danny" on CBS's The King of Queens and has also contributed as a writer. On TV, he's been featured in Men of a Certain Age, a Ray Romano creation, and had a special on Comedy Central, among other roles.

His film credits include roles alongside Hollywood stars like Matt Damon in Stuck on You and Adam Sandler in I Now Pronounce You Chuck and Larry. He's also been seen in Paul Blart: Mall Cop, Zookeeper, Poolboy: Drowning Out the Fury, and the upcoming film Grumpy Old Santa where he plays the role of Spike. Valentine made a cameo in Jerry Seinfeld's documentary, Comedian, and is a frequent contributor to E!'s Chelsea Lately and the Dusty Peacock web series on Crackle.