Jason Ritter (born February 17, 1980) is an American actor. He is known for his roles as Kevin Girardi in the television series Joan of Arcadia, Ethan Haas in The Class, Sean Walker in the NBC series The Event, Dipper Pines in Gravity Falls, and Pat Rollins in Raising Dion. He also played the recurring role of Mark Cyr in the NBC television series Parenthood, for which he received an Emmy Award nomination. In 2017, he starred in the TV comedy series Kevin (Probably) Saves the World. He served as the voice of Ryder in Frozen 2.
Ritter was born on February 17, 1980 in Los Angeles, California, to actors Nancy Morgan and John Ritter. He is also a grandson of actors Tex Ritter and Dorothy Fay. His stepmother is actress Amy Yasbeck. The actor has three siblings, including actor Tyler Ritter.
Ritter first appeared in the opening credits of his father's show, Three's Company. He was the little blonde haired boy running up to Joyce DeWitt in the petting zoo scene.