LL Cool J and his wife, Simone I. Smith, are paying it forward following her fight with cancer. 

ET's Nischelle Turner sat down with the couple as they opened up about their new campaign for the American Cancer Society, which aims to help people "Beat Cancer Like a Boss." Simone was diagnosed with chondrosarcoma, a rare bone cancer, in 2004, and is now in remission. 

"I was working out with my trainer, walking, talking, not paying no mind, walked into the waste basket and it hit that little knot. That sent me to the doctor, and that's when I found out I had a chondrosarcoma stage three tumor in my right tibia bone," Simone recalled. She went through a 15-hour surgery, during which her right tibia was removed, replaced with her left fibula, a still rod, screws, nails and micro veins from her other legs. "It was a two and a half year recovery, where I had to learn to walk again. I went from a wheelchair to two crutches, to one crutch to a cane."

"In that moment there, I was devastated," she added, tearing up. "I'm not going to get emotional!" 

Simone, who married LL (real name James Todd Smith) in 1995, called him her "rock." "I remember sitting in the doctor's office, and he wanted to give his fibula bone... because he felt that his fibula bone would be bigger and stronger." 

The rapper was also protective of his wife post-surgery; Simone recalled him asking visitors to compose themselves before seeing her. "Todd would tell them... 'You can't go in there crying,'" she revealed. 

"Because you need positive energy," he explained. 

Simone has been cancer-free for the last 14 years, but decided to use her experience to help others. She created her own jewelry line in 2011, with a portion of the proceeds going to fight the disease, and this year, she and LL have collaborated with some famous friends -- like Mary J. Blige, Remy Ma, Salt-N-Pepa, Jhene Aiko, Jordin Sparks and more -- on the "Beat Cancer Like a Boss" campaign. 

"The campaign is 'Beat Cancer Like a Boss,' and when it comes to that, she's definitely been a boss," LL said. "I think that so many people, if you can inspire others to learn more, dream more, do more, that's being a boss and that's why we did this campaign for the American Cancer Society and for Simone Smith, her jewelry, which a portion of all the proceeds go to the ACS." 

"Mary and I, we actually became friends the year that I was diagnosed and I remember when I was in the hospital Mary came to see me and she sent me flowers everyday," Simone revealed, adding that their friendship has now turned into a professional collaboration, Sister Love. "That's my girl." 

One of the first pieces of jewelry Simone designed was inspired by herself, post-surgery. "It's called the sweet touch of hope. It's [designed after] the lollipop tattoo that was on this leg," she explained. "During my surgery, it was disfigured cause they had to do skin graft, and after the surgery, it looked like somebody took a bite out of it. The candy represents how sweet life is. The bite represents what cancer does to the individual, their family, their loved ones."

LL has made sure that his and Simone's children, Najee, Italia, Samaria and Nina, have grown up knowing how to support their parents, each other, and the future. "The world should be better because you were here. You should be making a real contribution to society," he said. "I'm still blue collar, you know what I'm saying? I'm not buying into the Hollywood stardom money thing. Don't get me wrong, I like paper like everybody else... But the kids, they gotta contribute."

The rapper said that his wife's fight with cancer taught him about "just being supportive." 

"I learned that you got to be grateful, and you can't take things for granted. I learned that left turns could come, right turns could come. You can't always see around every corner, but you just have to have faith and you have to have gratitude, you got to roll with humility, you got to believe," he expressed. "I believe in God strongly, and you got to believe in yourself too."

That message is one that Simone wants families living with a diagnosis like hers to internalize. 

"Have faith," she said. "Find your inner strength. Be confident." 

See more on the couple in the video below. 

RELATED CONTENT: 

Radiohead, Bon Jovi and LL Cool J Among the 2018 Nominees for the Rock and Roll Hall of Fame

'Stranger Things' Kids Channel LL Cool J and Weezer on 'Lip Sync Battle' -- Watch!

Chris O'Donnell on Why You Don't Mess With LL Cool J: 'He is a Force to Be Reckoned With' (Exclusive)