Kevin was born April 26, 1965, to Janet and Joseph Valentine Knipfing. He attended Cortland University where he played fullback on the football team while majoring in sports management. He realized after 3 years that this wasn't the path for him. After returning home, he decided to go back home and to break up the monotony of the summer, he joined a community theater. During a play in which he had a comedic role, he so enjoyed the crowd reaction, that he joined his brother's (comedian Gary Valentine's) improv group. He began going to clubs with Gary and realized he, too, had the knack for comedy. He has performed standup up for about 11 years. It was on the comedy circuit that he met Ray Romano. While Ray was getting a big break with his own sitcom, Kevin was getting recognition on "Star Search" (1983). After appearing on "The Tonight Show with Jay Leno" (1992), his big break came at the 1996 "Just for Laughs" Montreal Comedy Festival. Afterward, he landed a recurring role on Ray's sitcom, "Everybody Loves Raymond" (1996). He has since received his own sitcom "The King of Queens" (1998).