NEW YORK — As investigators look into whether a medical problem may have caused a motorist to plow into a group of New York City trick-or-treaters, killing a 10-year-old girl and two others, mourners remembered the victims.

“I had a lot of dreams for Nyanna,” Natalia Perez said the day after her daughter, Nyanna Aquil, was pronounced dead at a hospital. The victim’s 3-year-old sister also was hospitalized.

Perez’s 65-year-old father, Louis Perez, suffered severe head trauma and died at the scene Saturday night when the car jumped a curb in the Bronx, leaving behind mangled bodies and bloodied costumes as neighbors ran to help.

Another man, 24-year-old Kristian Leka, also was killed.