Michael Jackson's sons commemorated his 65th birthday by surprised his fans in Las Vegas at an event honoring the late King of Pop.

Prince Jackson, 26, and 21-year-old brother Bigi Jackson—nicknamed Blanket for years—attended the Michael Jackson Blue Sapphire Birthday Celebration Aug. 29. The immersive event, held at the Mandalay Bay Resort and Casino, was co-hosted by his estate and Cirque de Soleil, which recently celebrated the 10th anniversary of its Michael Jackson: ONE show at the hotel.

The brothers' night out marked a rare public appearance for Bigi, who has largely kept out of the spotlight since Michael's 2009 death at age 50.

And in addition to honoring the "Thriller" singer at the show, Prince posted a tribute to his father on his father on his Instagram. "Happy birthday dad," he wrote, alongside a throwback pic of himself, Bigi and their sister Paris Jackson, 25, with the singer. "I miss you and I love you. You may be gone but not forgotten. You're in our hearts each and every day."

Paris also took to Instagram on Michael's birthday, defending herself amid criticism from fans who harassed her over not sharing a tribute post to her father.

"So today is my dad's birthday and back when he was alive, he used to hate anybody acknowledging his birthday," Paris began the Instagram video. "He actually didn't want us to even know when his birthday was because he didn't want us to throw a party or anything like that."

She continued, "That being said, social media is apparently how people express their love and affection these days and if you don't wish someone a happy birthday via social media, it apparently means that you don't love them and you don't care about them. There have been times where I don't post anything for my dad's birthday and people lose their f--king minds."

However, she proved that even without a dedicated social media post, she was keeping her dad's spirit alive on his birthday.

In fact, after defending herself from internet trolls, Paris, who is touring with Incubus, played a video of herself paying tribute to her father at a concert that same day.

"He would have been 65 years old today and he put 50 years of blood, sweat and tears and love and passion into doing what he did, so I could stand up here on stage, in front of you, and scream into a microphone," she said onstage. "So I owe everything to him."

For a look back at Michael's kids over the years, keep reading:

Prince Jackson and brother Bigi Jackson (nicknamed Blanket for years) appear Aug. 29, 2023 at the Michael Jackson Blue Sapphire Birthday Celebration at the Mandalay Bay Resort and Casino, an event co-hosted by his estate and Cirque de Soleil, which also recently celebrated the 10th anniversary of its Michael Jackson: ONE show.

Prince and Bigi appear at their family's annual Thriller Night celebration in 2022.

Prince and Paris attend the Michael Jackson Diamond Birthday Celebration at the Mandalay Bay Resort and Casino in Las Vegas.

Prince and Paris appear together at the 2022 Harold and Carole Pump Foundation Gala at The Beverly Hilton in Beverly Hills, Calif. in August 2022.

Prince and Paris appear in a YouTube video in 2021.

Prince and Bigi appear at their family's annual Thriller Night celebration in 2019.

The two pose at Prince Jackson's Heal LA and TLK Fusion Present The 2nd Annual Costume For A Cause at Jackson Family Home on Oct. 27, 2017.

Walking hand-in-hand, the two attend the mothers2mothers and The Elizabeth Taylor AIDS Foundation Benefit Dinner on October 24, 2017 in Beverly Hills, Calif.

Prince wrote, "It was an honor to be a part of @officialsiggyjackson wedding with my sis @parisjackson."

The sibling showed off their silly side over the summer on Instragram.

The trio of siblings arrived at the Michael Jackson: The Immortal World Tour in Los Angeles on January 27, 2012. 

Prince and Paris attend the hand and footprint ceremony at Graumann's Chinese Theater in Los Angeles January 26, 2012.

The duo stood together as they attended the press conference for Goin' Back To Indiana: Can You Feel It at the Majestic Star Hotel Lakeshore Ballroom on August 29, 2012 in Gary, Indiana. 

On Aug. 30, 2012, the siblings attended the St. Paul Saints Vs. The Gary SouthShore RailCats baseball game at U.S. Steel Yard in their father's hometown of Gary, Indiana.

The trio appeared on stage during the memorial service for their father at the Staples Center in Los Angeles on July 7, 2009.

The kids celebrate together with dad in this throwback pic shared by Prince.

Prince shared this family photo on what would have been Michael's 64th birthday on Instagram.

Prince, Paris and Bigi, then nicknamed Blanket, appear with their dad in this throwback pic the eldest of his children shared on what would have been his 64th birthday in 2022.

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