Chicago Bulls forward Taj Gibson called his slain nephew the "future of our family" at the funeral for the 6-year-old on Friday in New York.
Prince Joshua "P.J." Avitto was stabbed to death on Sunday in an apartment elevator.
Among the 1,500 friends, relatives and mourners who attended the service at St. Paul Community Baptist Church in East New York was Bulls coach Tom Thibodeau.
The 6-foot-9 Gibson said his nephew loved superheroes.
"The main thing I can always remember is he'd say, 'I'm Superman, pick me up,'" Gibson said.
Gibson said after the service that he would miss the youngster who liked to ask him about basketball at family gatherings
"It's going to be hard. It's going to be real hard not having that young face running around the barbecues, saying, 'Pick me up,'" Gibson said. "It really hits home."
New York City Mayor Bill de Blasio and the Rev. Al Sharpton also paid their respects.
Daniel St. Hubert, a 27-year-old ex-convict, was arrested Wednesday and charged with the murder of the boy and the attempted murder of 7-year-old Mikayla Capers, who survived the stabbing attack. Wielding a steak knife, St. Hubert stabbed each child multiple times, according to police, and then fled from the building near where the children had been playing.