After being abandoned in the foyer of a Brooklyn building by her mother in 1996, a young woman used genetic testing to gain a poignant introduction. Corey Kilgannon of The New York Times reports.

On a frigid December night in 1996, a young woman ducked into an apartment building in South Brooklyn and left a shopping bag in the foyer.

Inside was a 3-day-old girl, along with a remorseful, but tender, letter from the woman saying that said she hoped for a better home for her newborn daughter, Sarah, whose name was written in neat print.

That name, in similar