updated 10/23/2011 AT 9:00 AM ET
•originally published 10/23/2011 AT 10:30 AM ET
Get ready to feel old.
Jonathan Lipnicki, the inquisitive tyke who charmed Tom Cruise’s Jerry Maguire with his oversized glasses and musings on bees’ ability to smell fear in the 1997 film, turned 21 Saturday.
The actor is celebrating the milestone birthday in Las Vegas with his parents, his sister, an aunt, three cousins and an assortment of friends.
The Lipnickis celebrated Friday with a dinner at Tao before arriving a little after midnight at the Surrender Nightclub at the Encore, where he enjoyed vodka cocktails with his buddies late into the night.
The party continued Saturday with a cake and dinner at Lavo.
Virtually unrecognizable since his days starring in films like Stuart Little and Like Mike, Lipnicki has spent a bulk of his time since graduating high school three years ago studying and fiercely working out, spending six days a week weightlifting and training in jujitsu.
“I live in Hollywood,” Lipnicki, who clocks in at 5’7” and 150 lbs., told PEOPLE in September. “Go three feet and you will run into someone more cut and better looking than me. For me working out is more about keeping my temperament great. Jujitsu and lifting keep me very even.”