Alex Heard’s mom, Kelli, was his best friend.

“When I was younger, I would lie on her and watch TV,” he recalls. “She always wanted to hear my stories and give me advice.”

Unfortunately, Kelli was diagnosed with advanced kidney cancer called clear cell renal cell carcinoma in October 2018. And, after undergoing immunotherapy and chemotherapy, and participating in clinical trials, she passed away 13 months later. But in that...