Nikita Grebelsky, of Forest Hills, died Wednesday from a bullet wound he sustained when a gunman opened fire in the livery cab in Flatlands on August 18, police said.
Michael Magnan, 19, was arrested after the shooting.
Authorities believe Magnan pulled a gun while the livery cab was stopped at Utica Avenue and Avenue M and demanded money from the driver. After the driver refused, a fight broke out and the cab peeled off, police said.
That's when Magnan allegedly fired a .30-caliber handgun at the livery cab. Grebelsky, who was riding in the backseat with his sister, Elizabeth Filatova, 25, was struck in the head.
No one else was injured.
He was critical in Kings County Hospital for four days before succumging to his injuries.
Magnan, who has seven prior arrests, had been charged with attempted murder, assault, attempted robbery and weapons possession. Those charges could be upgraded now that Grebelsky has died.