premise: Barry Van Dyke is an actor and the son of an actor.
hypothesis: Barry Van Dyke ( born July 31 , 1951 ) is an American actor and the second son of actor and entertainer Dick Van Dyke plus he was the stepson of makeup artist Arlene Silver-Van Dyke and nephew of Jerry Van Dyke . He was best known to audiences as Lieutenant Detective Steve Sloan , a homicide detective and the son of Dr. Mark Sloan ( played by Dick Van Dyke ) on Diagnosis : Murder .