Houston police said the baby's parents were having a party at a home in the 2700 block of Woodland Park Drive when one of the attendees hit the 1-year-old as he was leaving around 1:15 a.m. Monday.
The 33-year-old, who was driving a white Alfa Romeo Stelvio, stopped and transported the baby and his parents to HCA Houston Healthcare West, where the child was later pronounced dead.
Investigators determined that the driver was not impaired. He was questioned and released.
Police said no charges were filed. The investigation will be referred to the Harris County grand jury.