Turning 40 in style! Reese Witherspoon enjoys a private concert from Taylor Swift as she parties with Kate Hudson and Jennifer Aniston at her birthday bash
She doesn't actually hit the Big 4-0 until Tuesday.
But that didn't stop Reese Witherspoon getting an early start on her birthday at a massive party for her family and all her star friends at the Warwick, in Hollywood, on Saturday.
Her pal Taylor Swift even jumped on stage to sing her hit, Shake It Off, for the actress and fashion entrepreneur.
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Ready for fun: Reese Witherspoon couldn't resist taking this photo as she, her CAA agent husband Jim Toth and her mother Betty Witherspoon drove to her 40th birthday party at the Warwick, in Hollywood, on Saturday
Reese arrived with her CAA agent husband Jim Toth and her mum Betty Reese, according to People.
The Legally Blonde star shimmered in a black, sequin-covered mini-dress, that hugged her slender figure and showed off her shapely legs.
The petite celebrity added to her height with a pair of silver high-heeled, strappy sandals
Great gift: Taylor Swift surprised the star by hopping on stage to sing her hit Shake It Off, with Keith Urban on guitar, and Kate Hudson captured the moment
Heartfelt message: Kate posted a slew of snaps on social media at the event including this second shot of Taylor and Keith
Snuggling up: Taylor, Cheryl Strayed and Laura Dern helped Reese celebrate her 40th in this Instagram posted by Cheryl
And she was quickly joined by an A-list of Hollywood guests including Kate Hudson, Courteney Cox, Jason Bateman, Jennifer Aniston and husband Justin Theroux, Matthew McConaughey and wife Camila Alves, Robert Downey Jr. and wife Susan Downey, Nicole Kidman and husband Keith Urban and Tobey Maguire and wife Jennifer Meyer, Cheryl Strayed and Laura Dern.
Kate seemed to have a particularly good time, taking to Instagram in the early hours of Sunday morning to post a collage of snaps of herself and Reese with gal pals.
Gal pals get together: Betty, second from left, Reese and Kate, far right, cuddled up with friends in Kate's Instagram snap.
Having fun: This, and two other pictures, were part of a collage Kate posted early Sunday morning, saying 'Love you #ImSoExcitedToGetIntoBedIDontEvenKnowWhatToDoWithMyself #NotWashingMyFace #GoodNight'
Belting it out: Writer Derek Blasberg captured Reece's performance, saying, 'You can take the girl out the South, but you can't take Sweet Home Alabama out the girl! HAPPY BIRTHDAY @reesewitherspoon (cc @keithurban)'
The 36-year-old captioned it: 'Happy Birthday gorgeous girl @reesewitherspoon !!! Love you #TequillaFirst #PostingLater #ImSoExcitedToGetIntoBedIDontEvenKnowWhatToDoWithMyself #NotWashingMyFace #GoodNight.'
Meanwhile, Taylor wasn't the only singer to hit the stage.
Reese sang her signature song Sweet Home Alabama, from her 2002 film of the same name, with rocker and American Idol judge Keith on guitar.
The moment was captured by author and Vanity Fair writer Derek Blasberg, who posted it on Instagram.
Silly selfie: The 36-year-old actress shared this party photo of herself and Reese on Snapchat
Belted up: Kate was obviously not happy that she was running behind time for the party's 7.30pm start
He captioned it: 'You can take the girl out the South, but you can't take Sweet Home Alabama out the girl! HAPPY BIRTHDAY @reesewitherspoon ❤️ (cc @keithurban)'
And Reese shared a video clip of herself shaiking a leg with her mum, saying: 'Crazy on the dance floor? ?????? #BirthdayWeekend #MomsInTown ????'
The Cruel Intentions star will likely have a quieter party on Tuesday with her three children, Ava, 16, and Deacon, 12, with ex-husband Ryan Phillippe and three-year-old son Tennessee with Jim.
Shaking a leg: The beautiful blonde posted an Instagram video of herself and her mother Betty dancing
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