For one Fountain Valley couple, the walk is driven by the memory of their son and a mission to help other young people facing cancer.
The CHOC Walk begins early in the morning, bringing together families and supporters with personal reasons for taking part.
"Everyone has a reason to be there and Carter is our reason why," Jamie Ankeny said.
Doctors diagnosed her son, Carter Ankeny, with Acute Lymphoblastic Leukemia a month before his fifth birthday.
His mother said Carter met the challenge with optimism and adventure.
"He just has this infectious laugh and smile, and joy and zest for life," she said.
Carter's parents, his sister and the people he met at Rady Children's Health in Orange County, formerly CHOC, followed his positive lead throughout his treatment.
Acute Lymphoblastic Leukemia is one of the most curable forms of childhood cancer, and Carter initially responded well.
"He was able to go back to kindergarten, he was able to go back to baseball," Jamie Ankeny said.
In July 2017, the cancer returned. Another round of treatment did not stop Carter from participating in the CHOC Walk the following month. He led his CarterStrong team and embraced the experience.
"Being there in the wee hours of the morning and seeing everyone gather there on Main Street USA," she said.
Carter was doing well, making it unthinkable for his family when he suddenly died in October of that year from a rare complication of chemotherapy.
"So he was in remission when he passed away, so we feel, you know, he beat the cancer," his father, Tim Ankeny, said.
His parents said Carter told them he wanted to pursue a medical career so he could help other pediatric patients.
"Carter always talked about wanting to grow up and be a doctor at CHOC and cure cancer," his mother said. "He didn't have that opportunity and so now we take that on as, you know, our responsibility to do that for him."
The couple continues to raise money through the CHOC Walk for the hospital Carter loved, and for research.
"Partnering with Rady Children's Health, who is one of the top research children's hospitals, will now bring those research opportunities and treatments to CHOC," Jamie Ankeny said.
The 34th CHOC Walk in the Park, presented by Disneyland Resort, is scheduled for Sunday, Aug. 2. Team CarterStrongForever hopes others will join them.
Registration is now open at CHOCWalk.org, where you can also learn how to donate.