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Mutombo first met Matadi in Congo, where the former pro basketball star’s foundation built a hospital, the television station reported. Doctors repaired a cleft lip for Matadi but were unable to operate on the tumor.
"(It’s) very difficult as a father to see a child who is 8 years old who is born like all of us but has not gotten opportunities," Mutombo said.
Mutombo's foundation sponsored Matadi's flight to the United States, where doctors at the Osborne Head & Neck Foundation in Los Angeles are performing the surgery for free.
"He is suffering from a life-threatening illness and we are here to help this little boy and Mr. Mutombo's foundation save this little boy's life," Dave Dell of the Osborne Head and Neck Foundation told KABC.
"Hopefully (the surgery will) change the life of this young man and go back to living a normal life," Mutombo told the television station.
Matadi will stay with his father, who accompanied his son to the United States, at the Ronald McDonald house for free while he recovers from his surgery.