Ben Geller is the son of Ross Geller and Carol Willick. He is born in "The One With The Birth", and lives with his mother and her wife, Susan Bunch. Ben is played as an infant by Michael Gunderson, by twin brothers Charles Thomas Allen and John Christoper Allen from Season 3 to 5, and by Cole Sprouse from Season 6 to 8.
Ben is Ross' only son from his first marriage, but was born after Carol and Ross' divorce was completed. He is raised by his mother Carol Willick and her lesbian partner, Susan Bunch, so Ross only gets to 'babysit' Ben on occasion. Ben is rarely seen with the other Friends, who were present at (or very near) his birth. This causes him to sometimes mix up their names, like calling Rachel Phoebe. The gang all adore Ben, but prove pretty unreliable babysitters, not just Joey and Chandler (who lose Ben on a bus while Joey does his babe-magnet flirting) but even devoted and domestic aunts Monica and Rachel, who teach Ben pranks that end up being pulled on his parents.
Being spoiled by three rivaling parents, and bright by nature, Ben grows up as an amusing rascal. Although he seems to get on with the other friends, as well as his father, Ross, he was once both bemused and frightened by Phoebe when he witnessed her losing her temper over an arcade game in Monica's apartment. Apart from that one incident, there is no evidence of him ever becoming upset with any of the Friends.
- In "The One With The Sonogram At The End", there were arguments over what Ben's surname was to be; Carol and Susan originally wanted him to have the surname 'Willick-Bunch' which caused Ross to angrily insist that they include his own name. In later episodes, his surname is simply Geller, in contrast to the names of his mothers. It was never shown how they decided on his last name.
- In "The One That Could Have Been, Part 1", Ben's name is still Ben, even though Susan was not present at Ben's birth and the events concerning his name in "The One With The Birth" couldn't have happened.
- While his parents initially could not agree on a name, they eventually came to "Ben" when Phoebe (who is wearing a janitor's uniform with the name tag "Ben") lectures Ross and Susan on how lucky the baby is for having such loving parents.
- When he was a baby, the Allen twins started talking, which caused problems as he had to be quiet in the scene.
- In "The One Where Old Yeller Dies", Ben says his first word which is "Hi".
- Ben's age is meant to be six in "The One Where Joey Dates Rachel", but it was said he was seven.
- Ben is said to have been John Travolta's favorite character.
- Ben's godfather is Chandler Bing, as said in "The One Where Rachel Smokes".
- Ben mysteriously vanishes from the show shortly before the birth of his half-sister, Emma. He is never seen again, and mentioned only rarely, with several characters seeming to forget he exists (such as Ross' father talking about how Emma is his first grand child). This is never explained, and has led to many fan theories as to why he does not appear after that point.
- Throughout the show, he never meets his half-sister, Emma, which dismays fans very much. However, it is possible the two met off-screen.
- When he was little, Monica accidentally banged his head against a beam in her apartment while playing the airplane game in "The One With The Giant Poking Device".
- In "The One With The Holiday Armadillo", despite his father's Jewish heritage, Ben would rather celebrate Christmas instead of Hanukkah, which initially disappoints Ross.
- Ben Geller would be 25–26 as of 2021, three years younger than Cole Sprouse, who played him in seasons 6–8.
- In a 2019 interview, actress Jane Sibbett thought by that time Ben would be in college, where his mothers frequently worry about him (source).
- In the "The One With The Sonogram At The End", it show that if the child was a girl, Susan and Carol would have named her Helen.
- "The One With The Birth"
- "The One With The Breast Milk"
- "The One Where Heckles Dies"
- "The One With Phoebe's Husband"
- "The One With Five Steaks And An Eggplant"
- "The One With The Baby On The Bus"
- "The One Where Ross Finds Out"
- "The One With The List"
- "The One With Phoebe's Dad"
- "The One With Russ"
- "The One With The Lesbian Wedding"
- "The One Where Old Yeller Dies"
- "The One With The Metaphorical Tunnel"
- "The One With The Giant Poking Device"
- "The One With All The Jealousy" (Mentioned only)
- "The One Without The Ski Trip" (Mentioned only)
- "The One With The Cat (Mentioned only)
- "The One With Joey's New Girlfriend"
- "The One With Rachel's New Dress"
- "The One Where Phoebe Hates PBS" (Mentioned in cut version) (Appears in uncut version)
- "The One With All The Resolutions"
- "The One Where Rachel Smokes"
- "The One Where Ross Got High" (Mentioned in uncut version)
- "The One That Could Have Been, Part 1"
- "The One Where Ross Meets Elizabeth's Dad" (Mentioned only)
- "The One With All The Candy"
- "The One With The Holiday Armadillo"
- "The One With The Truth About London"
- "The One After 'I Do'" (Appears in uncut version)
- "The One With Rachel's Date" (Mentioned only)
- "The One With Monica's Boots"
- "The One Where Joey Dates Rachel"
- "The One With The Cooking Class" (Mentioned only)
- "The One Where Rachel Is Late" (Mentioned only)
- "The One Where No One Proposes" (Mentioned only)
- "The One With The Pediatrician" (Mentioned only)
- "The One Where Monica Sings" (Mentioned only)
- "The One With the Donor" (Mentioned only)
- "The One In Barbados, Part 1" (Mentioned only) (Vaguely appears in photograph)
- "The Last One, Part 1" (Mentioned only)
|Whole show||Jack Geller | Judy Geller | Gunther | Janice|
|Season 1||Barry Farber | Carol Willick | Susan Bunch | Mr. Heckles | Paolo | Fun Bobby | David | Nora Tyler Bing | Ursula Buffay | Mindy | Ben Geller|
|Season 2||Julie | Mr. Treeger | Frank Buffay Jr. | Estelle Leonard | Richard Burke | Sandra Greene | Eddie Menuek | Leonard Greene|
|Season 3||Frank Buffay Jr. | Mark Robinson | Sophie | Isaac | Chloe | Alice Knight | Pete Becker | Kate Miller | Joanna | Doug | Bonnie | Phoebe Abbott|
|Season 4||Kathy | Mr. Waltham | Joshua Burgin | Emily Waltham | Stephen Waltham | Andrea Waltham|
|Season 5||Danny | Charles Bing | Gary | Mr. Zelner | Kim|
|Season 6||Janine Lecroix | Jill Greene | Paul Stevens | Elizabeth Stevens|
|Season 7||Tag Jones|
|Season 8||Dr. Long | Mona | Eric | Parker | Emma Geller-Greene|
|Season 9||Mike Hannigan | | Theodore Hannigan | Bitsy Hannigan | Amy Greene | | Gavin Mitchell | Charlie Wheeler|
|Season 10||Erica | Jack Bing | Erica Bing|