Dennis Rush, who played Lon Chaney Jr. as a youngster opposite James Cagney in Man of a Thousand Faces and one of Opie’s pals alongside Ron Howard on The Andy Griffith Show, has died. He was 74.

Rush, who was diagnosed with leukemia last month, lived in the San Diego area and died Saturday on the way to the hospital, actor-musician Keith Thibodeaux told The Hollywood Reporter. (Thibodeaux played Johnny Paul Jason, another of Opie’s friends, on The Andy Griffith Show, though he’s best known as Little Ricky from I Love Lucy.)

Rush also showed up from 1960-62 on seven episodes of Wagon Train — John Ford directed him in one — and from 1962-63 on three installments of Laramie. Both were Westerns from Revue Studios and NBC.

The freckle-faced Rush made his onscreen acting debut as Creighton Chaney, age 4, in Universal-International’s Man of a Thousand Faces (1957), starring Cagney as silent film star Lon Chaney (The Hunchback of Notre Dame, The Phantom of the Opera).

As Creighton grows up, Rush is succeeded by Rickie Sorensen, Robert Lyden and finally Roger Smith, who at the end will embark on his own career as an actor (and a starring turn in The Wolf Man!) using the stage name Lon Chaney Jr.