• Taylor Swift has the Most Watched Video on Vevo for "Blank Space."

Taylor Swift has the Most Watched Video on Vevo for "Blank Space." (Photo : YouTube/TaylorSwiftVevo)

Reese Witherspoon seemingly is one lucky lady as she got a private concert from none other than pop star Taylor Swift and Keith Urban, on the occasion of her 40th birthday party at Warwick in Hollywood on March 19, Saturday.

The actress rented out the entire venue for the evening of fun that included the presence of her star pals like Kate Hudson, Jennifer Aniston, Justin Theroux, Courtney Cox, Chris Martin and Robert Downey Jr., to name a few, US Weekly reported.

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While the party started at 7:30 pm with a live band playing sexy jazz music as the guests arrived, the high point of the party came when Swift and Urban took the stage to perform at a strip down version of mega hit number "Shake It Off."

The unlikely duo gave an amazing rendition, with Urban playing his usual guitar and Swift also joining him to play some tunes herself. Rocking a pair of gigantic black boots and a short LBD, the "Bad Blood" hit maker looked perfectly on point as a rockstar, and later, the "American Idol" Season 15 judge was joined by the birthday girl herself, who sang "Sweet Home Alabama"  for the star-studded crowd.

It seemed to be a fun-filled weekend for Swift as she earlier reported to have partied all night with friends at the OMNIA nightclub at the Caesars Palace Hotel & Casino in Las Vegas on March 18, Friday, as her boyfriend Calvin Harris played DJ.

The 26-year-old singer was present at the event along with Karlie Kloss, Serayah, Todrick Hall as well as brother Austin Swift, where she had a blast dancing and singing.

"Taylor wasn't on her phone and was just living in the moment," a source told E! News. "Toddy danced like there was no tomorrow just like Taylor did."                                        

Taylor always seems to have a good time whenever she drops in at her beau's event. She also attended a Las Vegas nightclub party where Harris DJed back on New Year's Eve.

Meanwhile, watch Taylor's hit number "Blank Space" below: