Reese Witherspoon celebrated her 40th birthday on Saturday which has a private performance by Taylor Swift and also a duet with Keith Urban.

The Legally Blonde star marks this milestone on Tuesday, but her family helped her end up in the party spirit a bit early by throwing a large bash in Hollywood the other day, which has a string of celebrity friends attending.

Guests with the event, held for the Warwick, included Kate Hudson, Matthew McConaughey, Robert Downey, Jr., Courteney Cox, Tobey Maguire, Jason Bateman, and Jennifer Aniston and her husband Justin Theroux.

Nicole Kidman seemed to be spotted in the party, where her husband Keith was portion of the night’s entertainment, alongside surprise performer New Romantics singer.

Birthday girl Reese, who arrived with husband Jim Toth, shared her excitement as she headed to your bash in the Snapchat video back with her mum Betty, who was simply featured nodding because the actress asked, “Are you gonna get crazy around the dance floor, Mum?”. She captioned the brief clip, “Crazy within the dance floor? #BirthdayWeekend #MomsInTown”.

Meanwhile, pal Hudson also used social networking to document the night’s celebrations, like the moment when Taylor was introduced for the stage to be with her unexpected appearance, singing an acoustic version of Shake It Off.

“This beauty gave just a little surprise for your bday,” Kate captioned one Snapchat video.

“Happy birthday Reese, we like you!,” she added alongside another.

Reese, who wore a sparkly silver dress, also got in about the fun by hopping onstage to become listed on country star Keith, who played guitar for the rendition of Lynyrd Skynyrd’s Sweet Home Alabama, which featured around the soundtrack to her 2002 romantic comedy of the identical name.

“It would be a great party,” the original source added. “When Reese left at 2am, she what food was in the best mood. You could tell that they had the top time celebrating her birthday.”