It happened June 1 in Kingwood Township, when trooper Michael Patterson stopped Matthew Bailly after a minor motor vehicle collision.
After learning Bailly was a retired Piscataway police officer, Patterson told him he was also from Piscataway.
State police said when Patterson named the block he grew up on, Bailly said he remembered the street because he helped deliver a baby there 27 years ago when he was a rookie cop.
He went on to describe the color, style of house, and the baby's name, Michael.
Trooper Patterson extended his hand and replied, "My name is Michael Patterson, sir. Thank you for delivering me."
Police said Patterson's mother had been out shopping on October 5, 1991, when she went into labor.
She barely made it home, and her husband called the doctor who then talked officer Bailly through the birth.
After they crossed paths once again, Patterson and his mother visited Bailly and his wife at their home.
The State Police related the story on their Facebook page: