How Robin Williams Helped His 18-Year-Old Co-Star Land Prom Date

— -- When "Night at the Museum: Secret of the Tomb" star Skyler Gisondo needed to ask a girl to prom, he knew just who to turn to.

Gisondo, 18, stars as Ben Stiller's son in the new movie and asked his onscreen father, along with the late Robin Williams, to help him out and posted the video earlier this year.

In the video, Gisondo says, "Hey Hil, how's it going? I have a question to ask you, but I'm going to need a little help from my friends." You can guess who his two friends were

The young actor spoke to The Hollywood Reporter Monday about asking his idol Williams, who died earlier this summer at the age of 63, to do him a favor, just months before his death.

"All morning, Robin was pitching more ideas. He was saying, 'Can I say this? Would it be appropriate to say this?' You're Robin Williams. You can say whatever you want!" he told the magazine of the 2:50 video. "I realized that was the most awesome three minutes of my life and I've accepted it will go downhill from there."

In the video, Williams couldn't be more excited to help his new friend out and says, "Yo, Hilary, will you go the prom with my man Skyler!?" Williams even jokes that Gisondo is a great "kisser."

The story only follows the dozens that surfaced after Williams' death Aug. 11 of the late icon and how he helped so many, either by supporting friends or helping those he barely knew.

"Robin was this bottomless reservoir of kindness and hilarity," Gisondo added to the magazine.