A little boy dressed head-to-toe in Prince attire for Halloween can now brag that the President of the United States sang “Purple Rain” to him.

Gary Williams Jr. said his niece and nephew were getting candy from the Obamas at the White House on Monday when Barack started serenading the little purple one. The video has since been shared thousands of times on social media.

“When @BarackObama sees your nephew dressed as Prince & starts singing Purple Rain! Yep, Best Halloween Ever,” Williams wrote.