Leo Dontenville was born on the May 24, 1887 in Dieffenbach-au-Val. Leo immigrated with his parents Nicolas Dontenville and Philomena Kleinprinze in November 1891. Like his brother Joseph, Leo helped their father deliver milk before and after school.
He married Babette Martin in 1916 and resided with his mother-in-law Anna Martin in Woodhaven, Queens, New York. Leo worked as a cotton broker for the Paine-Webber Company in New York City. Their only child, a daughter Jean Martin, was born on November 21, 1918.
In 1926 Leo and his family moved to Hamilton Square, New Jersey close to his father's farm. He and his family moved back to New York to the Woodhaven Community of Queens in the 1930's. Leo died on February 16, 1966 in Sarasota Florida. Nothing is known of Babette Martin or her date of death. Their daughter Jean Martin married Frank Siroky of Cape May, New Jersey.