Kim Henderson watched from the window of her mother’s house as her nephew, Guy Henderson Jr., got in his car with an acquaintance Monday afternoon.

Then she saw something disconcerting.

“While (Guy Henderson) was sitting in the car, I saw the other guy drop a gun out of his waistband and pick it up real fast,” she said.

Fifteen minutes later, Guy Henderson was shot to death inside his blue Kia SUV on an Algiers street, leaving his aunt and other family members reeling at the loss of the 27-year-old SUNO graduate, whose father met a similar fate 15 years earlier.

“Everybody says it was a set-up,” Kim Henderson said of the killing.

New Orleans police have yet to make an arrest or name a suspect in the shooting, which happened about 4:15 p.m. Monday in the 3200 block of Ptolemy Street.

According to police records, “an unknown vehicle pulled up alongside the victim and began firing.”

But Kim Henderson thinks the man who got into the car with her nephew was involved in his killing.

She said the motive might have to do with a falling-out between Guy Henderson and his ex-girlfriend.

Kim Henderson said the woman had broken the windows in her nephew’s vehicle days before as retribution for his breaking up with her.

According to Kim Henderson, Guy Henderson graduated from Edna Karr High School, where he was a star quarterback. She said he used to play Pop Warner football with receiver Mike Wallace, who now plays for the Miami Dolphins.

Guy Henderson received an athletic scholarship to Grambling State University in 2004, according to the high school’s website. He later transferred to Southern University at New Orleans.

Kim Henderson returned to the scene of the shooting Tuesday, scouring it for clues to what led to her nephew’s death.

She said he had never recovered from the murder of his father, who was gunned down 2 miles away 15 years ago.

According to media reports, Guy Henderson Sr. was killed in April 1999 in the 6400 block of Isadore Street by Nathaniel Thorton.

A police spokesman said at the time that the motive was a dispute over money Thorton claimed Henderson owed him.

“We must be cursed,” Kim Henderson said of her family.

A woman whose house is next to where Monday’s slaying occurred said Tuesday she was still shaken by the outburst of violence on her street.

Carla Williams said she was at home with her twin 3-year-old daughters and her mother at the time of the shooting.

“At first I thought they were shooting firecrackers, but then I realized it was gunshots,” she said. “It was over 10 shots, pop, pop, pop.”

Her mother, Gloria Williams, bemoaned the violence in the neighborhood while preparing food for New Year’s.

“We usually sit outside and let the kids play until 5 or 5:30 to wear them out,” she said. “Where the car hit, that’s where they love to play.”

Carla Williams said the fact that a murder happened feet from her doorstep has made her consider moving.

She said Guy Henderson’s relatives were hysterical when they arrived at the scene.

At one point, according to Carla Williams, a woman burst through the police line in an attempt to see Henderson’s body. She was rebuffed by a police officer.

Caitlin McNally contributed to this report.