The impish boy tossing the football to Walsh is Pedro, an eight-year-old boy from Guerrero, Mexico. Pedro has Hirschsprung’s disease, a birth defect that affects one in every 5,000 newborn babies. Hirschsprung’s sufferers are born without intestinal ganglion cells — the nerve cells that permit the large intestine to relax so that solid waste can pass through the colon. To remedy the condition, which is fatal if left untreated, doctors remove the inert intestinal tissue and reconnect the functioning portion of the bowel to the anus.

Walsh had Pedro transported to Avera McKennan Hospital and University Health Center in Sioux Falls for treatment when the boy was a newborn, housing him and his family nearby at Casa de Carlitos, where families from Los Cabos can live while their children are receiving medical care. The frequent back-and-forth travel between South Dakota and Mexico was fraught with challenges. Walsh remembers being stopped at airport security in Dallas; the baggage screeners removed two long stainless steel medical instruments used for Pedro’s treatment from Walsh’s carry-on bag and proceeded to question him.

Yet Hirschsprung’s disease isn’t Pedro’s only medical problem. He was also born without a pituitary gland, necessitating a drug and hormone regimen that costs approximately $30,000 per year. And he has a cleft palate, for which he is undergoing a series of reconstructive surgeries. By now, Pedro has spent so much time in Sioux Falls that he believes he is a South Dakota native, and he boasts as much to his friends back in Mexico.

Unfortunately, not all of Walsh’s efforts have such cinematic, feel-good endings. Walsh began his work with Los Cabos kids in 2002, when he was asked to help three young children who suffered from leukemia. When he realized the gravity of their situation, Walsh immediately made arrangements to transport the children to Avera McKennan to be treated by Marwan Hanna, M.D., one of the leading pediatric oncologists in the Midwest. But Walsh quickly encountered a maze of red tape when he attempted to secure visas for the children and their families. All three children died while awaiting their visas.

Walsh’s foundation and his work largely focus on the people of the southern tip of Baja California, a region of stark disparities. “As in much of Mexico, there’s a great contrast between wealthy and poor,” Riggs says. “In Cabo, it’s extreme. There are the resort areas that most people see, and then there are these huge barrios, where we do a lot of our work.”

Though Los Cabos is highly Americanized and a favorite hangout for celebrities such as Sammy Hagar, Jennifer Aniston, Jessica Simpson, and Brooke Shields, some of its health-care facilities lack even basic medical equipment and supplies. And given the area’s unusually high rate of pediatric leukemia, the children of Los Cabos suffer disproportionately.

Walsh is no stranger to cancer; his wife has suffered from various forms of the disease during the past 25 years. Her struggles are what sparked his passion to help kids. Walsh headed the Make-A-Wish Foundation in South Dakota for 10 years, transforming it into one of the top five chapters in the United States. “The two most important days of your life are the day you were born and the day you figure out why you were born,” he says. For Walsh, the latter happened the day he committed his life to working with children who have debilitating diseases.

With a $2 million annual budget, the Los Cabos Children’s Foundation has a mission to provide world-class medical care to the children of Los Cabos and to build a web of humanitarian support systems. It established the Santa Josefina Blood Bank, the only private blood bank in Mexico. It funds and develops Casa San Juan Diego, a community center. It also supports Mobilize Mankind, which provides motorized wheelchairs and prosthetic limbs to disabled children; Amigos de los Niños, a children’s clinic; and Red Autísmo, an organization for families with autistic children.

The foundation recently teamed up with two country musicians, Amy Grant and Vince Gill, to cohost the annual Amy and Vince’s Fred Duckett Challenge at the Querencia Golf Club, in honor of California real estate developer and Los Cabos enthusiast Fred Duckett. The event raises more than $1 million each year. With the help of the Questro Group, one of the largest local developers in Los Cabos, the foundation secured 50 acres of scrubland and will begin construction on Amy & Vince’s Spirit of Joy Children’s Cancer Center this spring. The foundation plans to transform the site into a children’s medical campus that will include a wheelchair manufacturing facility, a Ronald McDonald House family residence, a rehabilitation center, medical training facilities, and eventually a world-class hospital. The idea is to create a self-sustaining health-care system that is staffed with highly trained Los Cabos residents in order to serve those in need.

“The sheer fortitude these families have is amazing,” Riggs says. “They don’t give up. The mothers of these children will go to the ends of the earth to help their children. The goal of the foundation is to ensure that they don’t have to.”

For more information about the Los Cabos Children’s Foundation and to support its mission, visit www.loscaboschildren.org.