"She knows exactly who she is, and she's very passionate about this," Nolan Gould told PEOPLE of on-screen sister Ariel Winter
The Weinstein Company & Netflix's 2017 SAG After Party in partnership with Absolut Elyx
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Nolan Gould is endlessly supportive of on-screen sister Ariel Winter, but he says when it comes to the actress’ crusade to promote body confidence, she doesn’t need any help.

“Here’s the thing, because people always come up to me and they’re like, ‘Does Ariel come to you for advice or does she come seek solace…?,’ ” Gould told PEOPLE at the Elizabeth Glaser Pediatric AIDS Foundation’s 28th Annual ‘A Time For Heroes’ Family Festival.

The Modern Family actor continued, “I’m like, ‘She doesn’t need me!’ In that sense, she knows exactly who she is, and she’s very passionate about this.”

He added, “I don’t think there’s anything anybody could say that would make her second guess herself in that way.”

Winter has long clapped back at haters who comment on her body or style. She previously told PEOPLE, “My thing is that I feel good about myself, and that’s what’s important.”

RELATED VIDEO: Ariel Winter Defends Wearing Her Full-on Glam Dress to Modern Family Screening in Fiery Statement

“Ariel draws a lot of attention and sometimes criticism over the way she dresses and the way she presents her body, but I support her, I really do,” Gould said.

The newly 19-year-old actor also opened up about maintaining a normal life while starring on a hit TV show, revealing, “It’s really – having really good people around you.”

“This is like the number one thing I tell people who want to get into acting, if you don’t have a support system, a life outside of acting, then when acting falls, because it inevitably does — it rises and falls — sometimes it will be really hot for a moment then you won’t be. I tell people to have a backup, basically.”

Gould’s backup? A variety of hobbies and personal interests.

“I’m a big scuba diver, gamer, I love the outdoors,” he said. I have really great friends, a lot of them aren’t even actors, so I have something to fall back on outside of this world.”