Jennifer Garner and Judy Greer Celebrate 20 Years of Friendship: ‘Sure Am Proud to Be Your Friend’

Jennifer Garner is celebrating two decades of friendship with one of her besties.

On Thursday, Garner took to Instagram to shout out her close friend Judy Greer. Garner, 51, met Greer, 48, on the set of the 2004 age-swapping romantic comedy, 13 Going on 30. 

“Twenty years with my JG,” the Juno actress captioned the post, smiling next to her friend of two decades. “I sure am proud to be your friend. Happy birthday, @missjudygreer.”

While Garner and Greer may be close friends in real life, they met playing characters in an on-screen feud. In the beloved film, Garner played Jenna, a 13-year-old girl who woke up in the body of her 30-year-old future self, assuming the role of a high-power fashion magazine executive. Greer played Lucy, a socially fraught frenemy in both the teenage and adult storylines. 

The iconic comedy, which is available to stream on Max, also stars Now You See Me actor Mark Ruffalo and famed stand-up Jim Gaffigan. 

Back in 2022, Garner posted a commemoration of her friendship with Greer, this time to her Instagram story. Smiling outside on a sunny day, the Catch Me If You Can star wrote, “I am grateful for a walk with a girlfriend, always.” She proceeded to add, “Especially this one. I love JG.”

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Before that, Greer chatted with Insider, reflecting on meeting Garner for the first time.

"Meeting her was a treat. Who can ever say enough about her? She's literally like what everyone says, like the greatest of all time," she said.

"She was just a really great leader," continued Greer. "She never complained. She was never late to work. She was professional, but she was also crazy fun and, obviously, so talented. When you have someone like that as No. 1 on the call sheet, you really can't complain about anything. Like, you're an a--h--- if you do."

Meanwhile, Garner recently reunited with her 13 Going on 30 romantic interest, Mark Ruffalo, on the set of Netflix’s The Adam Project. Speaking exclusively with PEOPLE, director Shawn Levy and star Ryan Reynolds described arranging the on-screen reunion. 

"It was my wife who suggested Jen Garner to play the mom," said Levy. "I shared the idea with [Reynolds] and he loved it. He then, after the fact, pointed out to me that this was the 13 Going on 30 reunion. So even though it looks like the smartest marketing move ever, it was strangely accidental, but we got all the benefit of the chemistry that exists between Mark and Jen."

Added Reynolds, "They really had a beautiful — and still do — just a sheer chemistry that you can't create, it's just there."

"To reunite them in a different kind of time-travel movie, but one that's just as sweet and warm-hearted felt really... we just felt very lucky," said Levy.