Geri posted a snap of Brooklyn with Emma as well as a throwback to when he was a little boy.
She wrote: "Happy 21st Birthday @BrooklynBeckham, oh, how you've grown!"
Victoria looked to be having a ball, with the fashion designer pictured enjoying a sweet embrace with husband David, who grabbed her PVC-covered bottom.
Brooklyn's girlfriend Nicola Peltz, 25, also shared a video dancing with her future mother-in-law Victoria to Gloria Gaynor's I Will Survive.
"Learning from the queen herself," Nicole captioned the shot.
Harper, eight, also got in on the action with Stormzy.
"Harper Seven and Stormzy take over the dance floor," Victoria tagged a shot of them.
She added: "Thank you Stormzy!"