(1869–1923) Helen was born in Brooklyn. Her father was John Taylor Sherman, a descendant of Roger Sherman, signer of the US Constitution. She attended the Packer Collegiate Institute in Brooklyn. In 1897 she married George DuPont Pratt, whose father, Charles Pratt one of the founders of Standard Oil.

In addition to other philanthropic causes, both Helen and her husband were avid supporters of the suffrage movement. In addition to generous financial support, they frequently opened their home to fund raisers and activities promoting equality under the law.