In honor of the Legally Blonde star's 46th birthday, the Just Go With It actress shared an adorable series of throwbacks and behind-the-scenes footage of the two iconic stars over the years.
Their friendship actually spans decades, as Reese played Rachel Green's sister, Jill Green, in Friends.
WATCH: Reese shares incredible throwback of Jennifer for her own birthday
The star's post on Instagram starts off with a photo from The Morning Show duo's time on the legendary show, where, while in character, Reese is in distress as Jennifer points out something and Courteney Cox, Matt Le Blanc, David Schwimmer and Lisa Kudrow stand in the background.
Jen started off her caption by endearingly describing the Big Little Lies star as: "My little sister > co-anchor > partner in crime."
The behind-the-scenes video included in the post made it even cuter than it already was, as it showed the We're the Millers actress recording the set of The Morning Show and as her camera reaches her co-star, she says: "Reese, be my Valentine," and she blows her a kiss in return.
The sweet tribute
Fans flooded the comments with congratulatory messages as they fawned over the sweet pictures, writing: "Beautiful sisters! Happy birthday, Reese," and: "Aww love your friendship so much!!" as well as: "The best duo there is, I love you both sunshines!!!"
The caption ended with: "I LOVE YOU, you sweet ray of sunshine. Let the love pour in! Happy BIRTHDAY."
The two stars playing the Green sisters in Friends
The mom-of-three spent her birthday definitely feeling the love, and basking in the sun while on spring break vacation. She shared a candid video of herself dancing along the sand with a glass of rosé wine on her hand, the color of which perfectly coordinated with the sun as it came down on the water during sunset.
The star has more to celebrate than her birthday too, as she just revealed an exciting new project with yet another legendary star. "Dreams really do come true!" she wrote, as she announced that her media company, Hello Sunshine, would be adapting Dolly Parton and James Patterson's new novel, Run Rose Run, into a movie.
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