Britney Spears Celebrates 35th Birthday With Nostalgic Performance in Los Angeles -- See the Adorable Pics!

Happy Birthday, Britney Spears!
The pop princess turned 35 on Friday, celebrating the special day with a show stopping performance at 102.7 KIIS FM's Jingle Ball at the Staples Center in Los Angeles.
Proving age is nothing but a number, Spears showed off her incredibly fit figure in a lacy white crop top with feathered sleeves, black booty shorts, fishnet tights and thigh-high boots.
Photo: Getty Images
Her blond tresses were pulled back into her iconic pigtails from her "…Baby, One More Time" video, taking fans on a nostalgic journey as she performed classic hits like "Stronger," "I'm A Slave 4 ," "(You Drive Me) Crazy," and "Toxic."

The birthday girl also belted out tunes from her latest album, Glory, even bringing R&B singer Tinashe on stage to sing their catchy "Slumber Party" track live for the first time.
At one point in the show, host Ryan Seacrest surprised Spears with a three-tiered cake, featuring a giant "B" on top, as her dancers and the crowd sang "Happy Birthday."
Photo: Getty Images
"Thank you for the sweet birthday wishes!" Spears later wrote on Instagram. "Had an amazing day. Love you all."

ET's Katie Krause was backstage at the festive fête, catching up with Seacrest moments before the big surprise.
"I may have something up my sleeve for her on stage when we get out there," he teased. "It's her birthday, so when you have a birthday, you have to get something with your birthday. It's one of the two things -- a present or a cake."
"It's not a present, it is a cake, but don't tell her!" he added. "I'm going to try and get the whole place to sing, but shh. If she come [backstage], dont tell her."
Earlier in the day, Spears' friends and family took to Instagram to send the blond beauty well wishes.
Her younger sister, Jamie Lynn Spears, shared a sweet throwback pic, simply captioning it, "Happy Birthday to my big sister. Love you very much."

Paris Hilton also opted for an older photo, captioning hers, "Happy Birthday @BritneySpears. Sending you lots of love, happiness & well wishes beautiful #BirthdayGirl!"

See more star-studded birthday messages below.