Owen Cooper received a private message from Robert De Niro after the 15-year-old actor’s Best Supporting Actor win at the Emmys, his representatives and eyewitnesses said.

Cooper, the breakout star of Netflix’s four-part drama Adolescence, accepted the award on Sunday and was later handed a handwritten note by De Niro that read, according to attendees, “Good luck in the future. Stay humble.” The teen, who flew to Los Angeles for the ceremony with his parents, received a standing ovation as he took the stage and was presented the statuette by Sydney Sweeney.

Cooper won for his portrayal of Jamie Miller in Adolescence, a series filmed when he was 14 in which each episode was shot as a single take. The programme has drawn attention beyond entertainment coverage, prompting renewed public discussion about young men and online "manosphere" communities and attracting comment at political levels in the U.K. Cooper beat longtime film and television stars, including Javier Bardem, in a category viewers and critics described as closely watched.

De Niro, who had publicly supported Cooper earlier in the year, met the young actor in March on the BBC One Show and offered on-air encouragement. “Well, I think he’s off to a good start, that’s the main thing. And just keep at it. Keep at it!” De Niro said at the time, adding advice to “try to stay out of trouble and all that stuff and you'll do well.” Show creator and star Stephen Graham has said he compared Cooper to De Niro after the actor’s first audition.

The relationship between Cooper and several established actors extended beyond De Niro. Actor Jake Gyllenhaal surprised Cooper before the ceremony with a small talisman — a “lucky duck” Gyllenhaal said he had been given before his own Oscar nomination — a gesture noted by those close to Cooper as emblematic of industry support for the young performer.

Cooper’s parents, Andy, an IT worker, and Noreen, a carer, accompanied him to Los Angeles. Cooper has said he remains committed to his schoolwork and took a pile of assignments with him to secure permission from his local school while in the U.S.

Adolescence has been singled out for its formal daring and for the performance that turned the teenage actor into a breakout presence. Critics praised Cooper’s single-take scenes and the emotional intensity of his performance. The series’ cultural impact extended to public debate about masculinity and the online cultures that surround it, debates that contributors to the show and some lawmakers have referenced.

Cooper's schedule already includes further high-profile projects. He is attached to a film adaptation of Wuthering Heights alongside Margot Robbie and Jacob Elordi, and is lined up for the BBC series Film Club, representatives said. Industry observers say the combination of critical attention, peer support and Cooper’s youth has intensified focus on how the actor and his team manage the transition to wider success.

At 15, Cooper is among the younger Emmy winners in recent ceremonies. Colleagues and early supporters have urged caution and steadiness: De Niro’s note and on-air advice reiterated a common theme among veteran actors who have weighed in on Cooper’s rapid rise.

Cooper did not immediately respond to requests for comment, and representatives for De Niro declined to provide further details about the exchange beyond accounts from those at the event.