MTV has teamed with eBay for Charity to give The Challenge fans a chance to support Diem Brown's cause
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The Challenge family lost one of its most fearless members when Diem Brown died from ovarian cancer at age 34.

As the third anniversary of Brown’s death approaches, MTV has teamed with eBay for Charity to give fans a chance to support Brown’s cause while hooking them up with exclusive Challenge merchandise. Beginning Tuesday, lovers of the reality competition can bid on exclusive items such as signed jerseys worn by Dirty Thirty cast mates Leroy Garrett, Camila Nakagawa and Cara Maria Sorbello; the Skull Jar from Rivals II, and an autographed hat from Johnny “Bananas” Devenanzio’s personal merchandise line. All profits will go to Bright Pink, a non-profit focused on the prevention and early detection of ovarian and breast cancer in young women.

“This is a way for us to try and not just spread awareness but actually help and contribute to cancer research and, hopefully, a cancer cure one day,” Devenanzio, 35, tells PEOPLE. “We’re all such a close-knit bunch, that when she was going through the fight, it hit very close to home for all of us.”

Brown first appeared on Real World/Road Rules: Fresh Meat in 2006 and participated in five more competitions before ending her run with 2015’s Rivals II, during which she was airlifted from the Panama filming site to a New York City hospital when her cancer returned for a third time.

RELATED VIDEO: Diem Brown Dies at 34

“She didn’t let a whole lot of people know how bad it was until it was pretty much too late,” recalls Devenanzio, who also competed on Rivals II. “This girl was going through chemotherapy and fighting cancer for the third time, and she was still so optimistic in her outlook on everything. But that last time I saw her [at the hospital in New York], that energy and that aura that she gave off was already gone. Even though she still physically was with us, it seemed like cancer had already taken away what made her who she was.”

After Brown died on Nov. 14, 2014, members of the Challenge community coped in different ways. Devenanzio worked with MedGift — a site Brown had started to connect patients with those who can provide financial and emotional care — and helped fund the treatment of fellow Californian Kelsey Brown. Thanks to his efforts, the high schooler, whom he now considers a “really close friend,” has been in remission for almost two years.

Credit: The Challenge Facebook

But Brown’s on and off boyfriend Chris “CT” Tamburello nearly shut down following her death. “He went radio silent for a while,” Devenanzio says of his fellow Challenge champion. “Nobody really heard from him. Since then, he’s rebounded in a pretty positive way. He has a baby now. I think those things he wanted with Diem, but unfortunately she was taken from us a little bit too soon. But whether or not he’s participating outright, he does what he can in his own way to give back and keep her memory alive.”

Devenanzio adds that the whole cast continued to remember Brown while filming The Challenge, now in its 30th season.

“Diem is known for being such an upstanding, innocent girl that plays by the rules,” he says. “But Diem was one of the most conniving players who ever played the game. Because she was so sweet, she was able to get people to do what she wanted them to do. Now, if somebody pulls a really shady move or something like that, we’re always looking up at Diem being like, ‘You know she’d definitely appreciate that.’ ”

According to the six-time champ, Brown would’ve applauded his Rivals III upset, in which he denied Sarah Rice a share of $1 million when given the option to split the winnings with his partner last year.

“The people who knew Diem very well,” Devenanzio explains, “we’re like, ‘She’s up in heaven smiling down right now.’ ”

To bid on auction items, head to this Tuesday through Aug. 15.

The Challenge XXX: Dirty Thirty airs Tuesdays (9 p.m. ET) on MTV.