Britney Spears receives sweet 40th birthday serenade from Kate and Oliver Hudson

Britney Spears has some supportive— and musical— friends in sibling duo Kate and Oliver Hudson.

The pop princess, who turned 40 on Dec. 2 and celebrated her first birthday since her conservatorship ended, posted a video on her Instagram account that featured the Hudson siblings singing "Happy Birthday" in her honor.

Dressed casually in a black t-shirt and jeans and adopting a suave R&B style of singing, Oliver crooned "Happy Birthday." Kate looked on, wrapped in a cozy sweater and extending her hand to show off her brother's musical skills.

“Happy birthday dear Britney f***ing Spears,” Oliver added, spicing up the video as Kate's 3-year-old daughter, Rani, popped up in front of the camera. Dressed in an adorable green holiday dress, Rani did her best to joining in on the celebratory tune. Kate also joined in to harmonize for the big finale.

Spears was recently seen hanging out with Kate. Last December, the "Piece of Me" singer popped by the Almost Famous star's house to hang out during one of her infamous game nights. In an appearance on Watch What Happens Live, Kate said that Spears showed up with her longtime agent Cade Hudson.

"Two blondes... Too much fun," Spears captioned a photo of the two peering over their shoulders at the camera. "Loved hanging with you last night @katehudson!"

In her own photo of the event, Kate wrote, “That moment when @britneyspears shows up to your game night and you're all like #itsbritneybitch.”

Kate has long been a fan of Spears. At a pre-Oscar party in 2020, she brought down the house with a performance of “. . . Baby One More Time,” Page Six reported.

Spears has gotten plenty of support from Hollywood recently. On Friday, Paris Hilton shared that it has been 15 years since she was famously photographed in a car with Spears and Lindsay Lohan outside of the Beverly Hills Hotel. In a new episode of her podcast This Is Paris, Hilton reflected on how much their lives have changed since that infamous 2006 photo was taken.

"I saw Lindsay got engaged, and I know that we’ve had our differences in the past, but I just wanted to say congratulations to her,” Hilton said. “I am genuinely very happy for her, and it just makes me so happy to see. Fifteen years later, and so much has happened in the past two weeks. I got married, Britney got her freedom back and engaged. Lindsay just got engaged. I love seeing how different our lives are now, and how much we’ve grown up.”

The House of Wax actress said she now believes a lot of their problems at the time were "caused by the media."

"In the 2000s, that’s what it was all about. They loved pitting women against each other. Every single magazine cover would say, ‘So and so hates this person,’ ‘Feud,’ just causing more drama than there even was," Hilton explained.

One of the most vocal supporters of Spears throughout her battle to end her conservatorship has been Lady Gaga, who frequently shares how much Spears means to her.

At the House of Gucci premiere, Gaga gushed about Spears in an interview with Variety.

“Britney is, she’s a woman in this business that showed a lot of power in her sexuality, even in her youth, in a way that, I think for me as a young woman, was just so inspiring and empowering. And I’d like to say this, truly — we can all root for her, but the person who changed her life was her. So this change that’s happening for her, it happened because of her, I believe," Gaga shared. "I’m excited for her future and I wish her all the best.”

Spears was so touched by Gaga's statement that she declared her gratitude on an Instagram story.

“Thank you Lady Gaga for genuinely taking your time to say something so kind,” she said. “You made me cry! I love you!”

In response, the A Star Is Born actress told her “Live your best life. I prayed for the legal system to treat you like a person. You’ve now changed the course for women in this industry forever. You stood up for yourself and were so brave. Thank you.”

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