Christina Mauser and eight others — including Kobe Bryant and his daughter — were killed in a helicopter crash on Sunday

Matt Mauser is remembering his wife Christina Mauser, who died on Sunday in the helicopter crash that also killed basketball legend Kobe Bryant.

During an interview with CNN‘s Anderson Cooper on Tuesday night, Matt called his wife a “strong” and “powerful” basketball player and coach who was planning to celebrate her youngest daughter’s fourth birthday next week.

“My little one, her birthday’s next week, that’s the hard part,” Matt said, visibly emotional. “I’m trying to navigate that. I’d walk in and [my daughter] would call for mom … and now I walk in, she doesn’t call for her … I think she gets it, she knows we’re grieving.”

Christina and Matt also share a 9-year-old son and an 11-year-old daughter.

“It’s like a roller coaster ride in a lot of ways. I’m up, I’m down, I cry for no reason whatsoever and then I’m okay,” he said of coping with his wife’s death. “I woke up this morning and I said, ‘I think I’m okay,’ and then I walked out and I started to cry. And then I saw my kids and I started to cry.”

Christina Mauser
Christina Mauser
| Credit: Facebook

“The thing that hurts me the most, the thing that gets me the most — it’s not the big things, it’s not how good she was at basketball. The things that I miss the most are the tiny little things,” Matt shared. “My wife was not just focused on the big things, my wife was focused on the little things, and the attention to detail about what kind of food to give our kids, doctors, how she would research every disease that was out there. She was relentless, she was organized and detailed.”

“She was kind, she was funny,” he added. “Our goal was to make each other laugh every day.”

Christina was the girl’s basketball coach for Harbor Day School in Orange County, California, and was recruited by Bryant to coach one of the teams in his Mamba Academy, according to CNN. The team Christina coached was the one that Bryant’s 13-year-old daughter Gianna — who was also killed in Sunday’s crash — played for.

“She loved three things so much: her husband, her three kids, and basketball. That’s who she was,” a friend of Christina’s previously told PEOPLE.

“She understood the strategy of the game. She had famous athlete friends, but she didn’t brag about them. That’s not who she was. She was very humble. She didn’t name drop. She didn’t brag,” the friend said.

Kobe Bryant
Kobe Bryant with daughter Gianna
| Credit: Allen Berezovsky/Getty

John Altobelli, the head baseball coach at Orange Coast College, was also on board the aircraft, as was his wife Keri Altobelli and their daughter, Alyssa Altobelli, who was a teammate of Gianna’s.

Sarah Chester and her daughter Payton Chester of Orange County have also been identified as victims of the crash, as well as the pilot, Ara Zobayan.