Lots of times actor’s family members will have cameos: Jean Stapleton’s son had a walk-on as a Boy Scout in an ALL IN THE FAMILY episode, Charlton Heston’s son played the infant Moses in THE TEN COMMANDMENTS, one of Tony Shalhoub’s children was recently on MONK and had about one line- but I’m talking about “more than third spearcarrier from the left” roles.
Carroll O’Connor’s much troubled real life son Hugh (adopted, hence the lack of resemblance) was a regular as one of the deputies In the Heat of the Night. He was rarely the focus of the episode, but some weeks his part was bigger than others. Their characters weren’t related.
In ED WOOD Martin Landau portrayed Bela Lugosi, a performance for which he won an Oscar. His real life daughter Juliet Landau played Loretta King, a significant supporting role (she’s the actress who Ed mistakenly thinks is going to finance his movie). I can’t remember if they interact (Bela was the villain in the movie in which Loretta appears), but their characters aren’t related to each other.
In A TIME TO KILL Donald Sutherland plays Lucien Wilbanks, the alcoholic disbarred lawyer who’s mentor to the hero (Matthew McConnaughey). Kiefer Sutherland is Freddie Lee Cobb (the brother of one of the two men Samuel Jackson’s character murders as revenge for raping his daughter) who joins the KKK. The characters aren’t related and I don’t believe they interact.
In the TV series 3rd Rock from the Sun John Lithgow’s real life son- who looks a lot like him- portrayed one of his students, Leon, in many episodes. Usually it was just a bit part but a few times he had something to do other than just sit in his desk and look stupid and intimidated (the character was both). He and Lithgow were usually in the same scene and Ian looks a lot like him. (As Ian hasn’t done any acting since then and went to Harvard I’m assuming this was largely a “let’s earn some college/student loan payback money” thing.)
On the ANDY GRIFFITH SHOW, Ron Howard’s father and brother occasionally appeared. His dad had one minor speaking role as a bus driver or something, and was also a non-speaking guest at a party. Ron Howard’s brother on a number of occasions played Leon. Leon never did anything but stand on the street or sidewalk, eating a peanut butter and jelly sandwich, which he always offered to share with whoever said “hi” to him.
On one episode of MARRIED WITH CHILDREN, David Faustino’s (aka Bud Bundy) brother Michael played an attendant at a car wash. He looked a little bit like David F, but sounded exactly like him.
At the beginning of THE BREAKFAST CLUB, Anthony Michael Hall is dropped off at school by his real-life mother and sister.
Christopher Masterson of Malcolm in the Middle was a guest star on an episode of That '70s Show, on which his brother Danny Masterson was a regular. Their characters were not related in any way.
Brother and sister Harry and Daisy Earles played characters in Freaks that were unrelated - by blood, anyway.
In Ron Howard’s Apollo 13 his mother played Jim Lovell’s mother and his father played a minister at the house.
Tony Shaloub’s wife Brooke Adams played a stewardess that Monk tortured on a flight. She then played the role again on the 100th episode. Looks like she played two other roles on the show but I don’t remember them.
Three of Charlie Sheen’s relatives have appeared on Two and a Half Men, not as relatives of his character, Charlie.
[ul]
[li]Father Martin Sheen has appeared as the father of the neighbor, Rose.[/li][li]Brother Emilio Estevez has appeared as a friend of Charlie’s.[/li][li]Sam Sheen, Charlie Sheen and Denise Richards’s daughter, has played the daughter of Lisa (Richards).[/li][/ul]
She played a Sheriff out in some country backwoods town. She was dressed up completely differently to her Flight Attendant role, so it almost worked.
Two of the Wilson brothers, Luke and Andrew, played distinctly separate roles in Charlie’s Angels (one as Cameron Diaz’s love interest, the other as a Chauffeur). But as the Wilsons all look very distinctive, with the big chins and the teeth, it was a little bit obvious.
Martin Sheen’s daughter Renée Estevez had a minor recurring role on The West Wing (Nancy, one of the President’s clerical secretaries). I only recall her speaking once, something along the lines of “Good morning, Mr. President.” No important plotlines really involved her.
Dennis Weaver’s sons Robby, Rick and Rusty all had occasional bit parts on McCloud and Gunsmoke; Rusty was also in an episode of Gentle Ben. Except for one or two episodes of Gunsmoke, all of these were with their dad and none of them were as Chester’s relatives.
Rosanna Arquette was on Medium for something or other. Really couldn’t stand to watch it or remember what she played from what I did catch, but it happened.
When Buddy Ebsen was starring in Barnaby Jones, his daughter Bonnie was trying to establish herself as an actress. She was blonde and cute, and I remember her having a part in a short lived sit-com. She guest starred on Barnaby Jones, in a standard sexual victim role. I remember wondering what kind of father would think it was a good idea to put his daughter in public in that kind of situation, but I was young, naive and unaware of the lure of stardom.
Actually, imdb shows them together in 6 episodes of Barnaby Jones and 2 TV movies. And it lists Bonnie in a dozen roles over 20 years, which is much more of a career than I would have expected.
Broadcast News (1987)
Class (1983)
Cradle Will Rock (1999)
Grandview, U.S.A. (1984)
Grosse Pointe Blank (1997)
High Fidelity (2000)
Martian Child (2007)
Say Anything… (1989)
Sixteen Candles (1984)
War, Inc. (2008)
Little House on the Prairie had several examples. Melissa Gilbert played Laura Ingalls while her brother Jonathan Gilbert played Willie Oleson. Patrick Labyorteaux played Andy Garvey while his brother Matthew Laborteaux (note different spelling of surname) played Albert Ingalls. Michael Landon was Charles Ingalls while his daughter Leslie Landon played one of the schoolteachers, Miss Plum.