McIntire was the son of actors John McIntire of the television westerns Wagon Train and The Virginian fame and Jeanette Nolan, who made more than three hundred television appearances and was nominated for four Emmy Awards. He had a younger sister named Holly. McIntire appeared three times with both his parents on television, first on the March 1966 episode "Ill Wind" of the series The Fugitive, second time was in the November 1966 episode "Old Charlie" of the series Bonanza, third he starred in an episide of The Virginian with both parents, in Season 6, Episode 16, in an episode entitled Death Wagon, first aired on January 3, 1968. He appeared again with his parents in another episide of The Virginian, in Season 7, Episode 12, in an episode entitled Nora, first aired on December 11, 1968.