RJ Sy, of Tenafly, was also an honorary member of the Redrum Motorcycle Club.
TENAFLY -- The honorary New York Police Department officer mourned by hundreds Saturday never took a civil service test, made an arrest or carried a firearm.
He was five years old.
Richard Aiden "RJ" Sy wanted to be a cop when he grew up. When he was diagnosed with neuroblastoma, a childhood cancer, two years ago, local police took him under their wing.
So did the Redrum Motorcycle Club, whose members joined a procession that approached Our Lady of Mount Carmel Church early Saturday as bagpipes played and law enforcement officers lined the streets.
RJ, who died Tuesday, was remembered at a Catholic funeral Mass for the adventures he packed into five years: meeting Mickey and Minnie at Disney World; riding in police cars, on fire trucks and in an NYPD helicopter; being kissed and blessed by Pope Francis.
The church was filled with uniformed police officers, bikers in their club vests, and family and friends, some of whom wore Batman and Superman capes in honor of RJ's love for superheros.
His loss hit hard for the Redrum club, where the young Bergenfield resident was a de facto member. The group held its first of multiple bike rides to raise money for RJ in 2014.
After that, RJ became one of the guys -- test riding a motorcycle with his dad, pedaling a tricycle around Memorial Sloan Kettering Cancer Center in a Redrum vest and helmet, getting his own Power Wheels truck as a gift from the club.
Redrum members from chapters around the world donated blood in RJ's name. Some bikers gave to RJ directly.
"We just wanted him to know we were always with him," said Shawn Watson, a Redrum member.
Anthony Agosto, a biker from Brooklyn, said RJ was constantly in and out of the hospital. But each time a treatment ended, Agosto said, he bounced back like nothing had ever happened.
Dozens of Redrum members mounted their bikes after the funeral to join the procession to RJ's interment.
"For a bunch of tough, ruffian lunatics, we've all been crying all morning," Watson said. "And that's before we even got here."
RJ never got to work as a cop. Fr. Dan O'Neill, who presided at the funeral, said his role in life turned out to be different.
"His assignment, his duty," O'Neill said, "was called 'angel of mercy.'"
Marisa Iati may be reached at miati@njadvancemedia.com. Follow her on Twitter @Marisa_Iati. Find NJ.com on Facebook.