Police have charged a third person with stealing the watch from local musician and community activist Joaquin Rivera as he sat dying in a Northeast Philadelphia hospital waiting room last month.

Jannira Walker, 21, was arrested Saturday on charges of robbery, theft, and related offenses. Walker's last known address was the 1300 block of West Erie Avenue, but police said it was possible that she, like the others arrested in the theft, was homeless. She was arrested near the Frankford Transportation Center, just a few blocks from the hospital where Rivera spent his last hour.

Relatives of Rivera, 63, a popular high school counseling assistant and musician, are mourning the death of a man who they said lived to play guitar and connect with his community.

Rivera's watch has been recovered, according to police, and will be returned to the family.

Rivera's son, Joaquin Rivera, Jr., declined to speak any more about his father yesterday, saying he needed a break from the media attention the case has received.

"We buried my father Saturday, and we just need some time," the younger Rivera said. "This is very hard. He is missed by all of us."

He said his family has been overwhelmed with support.

Rivera went to the Aria Health-Frankford Campus before 11 p.m. on Nov. 29, reporting pain in his chest and left arm, then signed in to await treatment. About 10 minutes later, a security camera in the room filmed Rivera as he struggled to breathe, put his hand to his chest, and fell still in his seat.

Walker was in the waiting room with Martin Smith and Richard Alten, who were charged with theft last week. Police believe Smith took Rivera's watch from his wrist after Rivera became unconscious.

According to some witnesses, Rivera sat unnoticed for nearly an hour before hospital staff realized he had died. The case is being investigated by the state Department of Health, the hospital, and the Philadelphia Police Department.

Rivera's death has sparked outrage in the city's Latino community, with some calling for broad health-care reform. On Sunday, a group of Puerto Rican activists gathered in front of the hospital, demanding that the federal Office of Civil Rights investigate the death.

Contact staff writer Allison Steele at 215-854-2641 or asteele@phillynews.com.