He grew up in Morton Grove, Illinois,[5] where his father owned a plumbing supply business called Bilko and his mother was active in community theater.

[6] When Garlin was in sixth grade, his father sold his supply business and the family relocated to South Florida.

He attended Broward Community College, followed by a stint studying film at the University of Miami, where he first began to perform stand-up comedy.

[14] While living in Wrigleyville, Chicago during the 1980s, Garlin was briefly roommates with Conan O'Brien, who was then a comedy writer.

[12][14] Garlin was hired by comedians Denis Leary and Jon Stewart to help develop their specials.

"[6] Garlin has a variety of television and film appearances to his credit, as an actor and a stand up, including Dr. Katz, Arrested Development, Everybody Loves Raymond, Late Show with David Letterman, Tom Goes to the Mayor, The Life and Times of Tim, The Daily Show, Late Night with Conan O'Brien, and Entourage.

He had a recurring role on the series Wizards of Waverly Place as Uncle Kelbo, appearing in three episodes over the first three seasons.

He appeared as Sid, alongside Jennifer Aniston and Gerard Butler, in the 2010 comedy action film The Bounty Hunter.

His feature directorial debut, I Want Someone to Eat Cheese With (which he also wrote), premiered to favorable reviews at the 2006 Tribeca Film Festival.

[22] In 2006, Garlin directed This Filthy World, a one-man show performed by director John Waters.

[28] For the rest of the season, Garlin's character continued to appear on the show via outtakes, a stand-in, and CGI.

In July 2013, Garlin directed his second film, Dealin' with Idiots,[31] inspired by his experiences with his sons in Little League.

On December 3, 2021, Vanity Fair published an article detailing that Garlin had been under investigation for three years for "allegedly engag[ing] in a pattern of verbal and physical conduct on [the set of The Goldbergs] that made people uncomfortable".

The report found that he had used "inappropriate language" and engaged in "unwanted physical contact" on set such as hugging or touching others without their consent.

The twice monthly installments were recorded in front of a live audience at Largo at the Coronet in Los Angeles.

Every year on his birthday, he attends a game with his friend Kevin Cronin, lead singer of REO Speedwagon.

[citation needed] For a few years, Garlin lived with talk-show host Conan O'Brien.

In addition to epilepsy and attention deficit disorder, he has type II diabetes, which he controls with diet and exercise.

I haven't had sweets in almost three years because I know if I have one cookie, just like if an alcoholic has his first drink, I'm off to the races and I'm back eating sugar again.