The child was spotted around 5 p.m. Saturday in Lakewood.
The motorist, Cory Cannon of Eatontown, told the Asbury Park Press he saw the girl on Joe Parker Road and initially thought she was a toy. But when he saw the child moving, he got out of his car to stop traffic.
At that same time, a neighbor got the baby and returned the child home.
Authorities say the baby may have left through a door that was left open by an older sibling. A woman at the home called the matter “an accident.”
It wasn’t clear how long the child was on the roadway.
The case remains under investigation.
Information from: Asbury Park (N.J.) Press, http://www.app.com