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Jennifer Garner and Reese Witherspoon are the most supportive friends around.

The A-List BFFs have been close pals for years, and often post sweet and hilarious messages to each other on social media.

The latest came earlier this month when Witherspoon, 42, posted a picture on Instagram of a tabloid magazine cover that claimed she and Garner, 46, were both pregnant. The Oscar winner laughed off the rumors by pretending to offer Garner the chance to co-parent their “imaginary babies.”

“Hey @jennifer.garner! Can we raise our imaginary babies together?” Witherspoon captioned a photograph of the cover.

“We are going to be the cutest imaginary family!! I’ll just go ahead and move in now…” Garner replied along with several laughing and heart emojis.

Just a few days later, Garner donned a full marching band uniform for the second year in a row to play a sweet tune for Witherspoon’s birthday.

“Many moons ago, my high school marching band played this song for homecoming. Today I play it for my boo, @reesewitherspoon We have a groovy kind of love.️ Happy birthday, Lady,” Garner wrote alongside the video.

But besides their social media fun, the two are also often supportive and there for each other. Witherspoon was seen attending Garner’s 45th birthday party in April 2017, just days after Garner and ex-husband Ben Affleck officially filed for divorce after separating in June 2015.

Witherspoon also took to Instagram that year to wish her friend a happy birthday.

“Here’s lookin’ at you, Jen! Happy Birthday to my gorgeous friend #JenniferGarner who always laughs at my jokes and my bad dance moves!” she wrote.

And in Sept. 2018, Garner once again showed her support for her friend when she tried out Witherspoon’s new book, Whiskey in a Teacup, and found some helpful advice about how to hot roll hair, which she experimented with in a video shared to her Instagram.

Taking purple hot hair rollers and curling her brown hair around them, Garner looked in the mirror and said, “So far so good.” She then mirrored Witherspoon’s hot rollers and red lipstick look in the book to pick up her kids, laughing at how they will react.

WATCH: A Young Jennifer Garner Turned This Classic Southern Treat Into Her First Business

“Boy, are my kids going to be surprised,” Garner added as she shook her waves loose and exited the car.

In the caption of her video, the actress wrote, “My friend @reesewitherspoon has written a book full of so much— great food and recipes, insights, family, life lessons. It’s so so fun, check it out! Oh, and her hot roller tips are . #WhiskeyInATeacup#availabletomorrow#improudofyoulady#belikereese.”

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