Mason and Reign blew out the candles on the birthday cake together.
Kris Jenner took photos and videos on the dance floor at her grandson's birthday party.
Fortnite decorations adorned the entrance and all over the party.
Khloe Kardashian shared a photo of the dance floor at the party.
Kris rocked a Burberry coat and hat.
True Thompson smiled as she made her way around the festivities with her mom.
Lucky guests enjoyed a live DJ who helped get the dance party started.
People could play the video game on giant screens in the backyard.
Reign Disick, who shares the same birthday as his brother, took in the sights.
Mason and his friends enjoyed a delicious-looking two-tiered Hansen's cake.