The Mortimer Family

121806 article mortimer The Mortimer FamilyIf New York City has a reigning socialite in Tinsley Randolph Mercer Mortimer, it may be due in part to generations of Darwinian specialization among her new family.

“The Mortimers have married so many people in so many families, they’re often referred to as the ‘marrying Mortimers,’ because they often married very well,” said pre-eminent New York social chronicler David Patrick Columbia. “They think very highly of their genealogy and their family tree. They’ve always been a very social family, but they’re also extremely tight-lipped.”

A while back, Mr. Columbia attempted draw up the Mortimer family tree, but failed; no one would tell him anything, he said.

The Mortimer family traces its origins to John Jay, the nation’s first chief justice. One of the current generation, Robert Livingston (Topper) Mortimer, that trusty husband of Tinsley, is the great-grandson of Henry Morgan Tilford, a president of Standard Oil, and he bears as well the name of Robert Livingston, a drafter of the Declaration of Independence.

“There are so many of them. It’s very complicated,” said Christine Mortimer Biddle, who is the daughter of Katherine Mortimer and Oliver Cadwell Biddle. Mr. Biddle was of the Philadelphia Biddles, she said, a family whose very black sheep was madam Sydney Biddle Barrows. “They all married well and often, and had many children who also married well and often.” Her parents divorced, and Ms. Mortimer went on to marry tennis star Frank Xavier Shields—she was already his third wife—and later Richard Blaine. “In the world I grew up in, it was more unusual to stay married to the same person all your life,” she said.

Katharine Mortimer Blaine, who died three years ago, was one of six children of Stanley Grafton Mortimer and Kathleen Tilford. Ms. Tilford was the daughter of Henry Morgan Tilford.

“But I would say that generally, the Mortimers mostly stayed out of the media, because they had no reason to court the media,” said Ms. Biddle. The wives—like Babe and Tinsley—get written about plenty.

“Babe” started out Barbara Cushing before marrying Stanley Mortimer Jr., a stockbroker, in 1940. They had two children, Stanley III and Amanda. Babe and Stanley Jr. got divorced in 1946 and remarried within a year, natch: he to Kathleen H. Harriman, granddaughter of railroad tycoon E. H. Harriman, she to William S. Paley, who founded CBS. Babe, who worked as fashion editor at Vogue, was the socialite queen of her time. Truman Capote included her in his group of “swans.” She was one of those famous for saying, “One can never be too rich or too thin.”

Amanda did her part to keep the marrying tradition alive. She first got hitched to Carter Burden (the great-grandson of Cornelius Vanderbilt), who once owned The Village Voice and New York magazine and later became a New York City Councilman. She kept that name but next married Steve Ross, the Time Warner C.E.O. who died in 1992, and then she went on to have longtime relationship with Charlie Rose, which reportedly ended in 2005.

Her father, Stanley Jr., who died in 1999, had five siblings, Henry, Richard, John Jay, Katherine and Eve.

John Jay is the father of Topper, and Eve married Clarence Pell, whose family helped settle upstate New York, and later Lewis Cass Ledyard, whose father founded the law firm Carter, Ledyard & Milburn.

“I’ve always been fascinated by privilege,” said Eve Pell, daughter of Eve and Clarence. Ms. Pell, who lives in San Francisco, recently finished a biography of both the Pell and Mortimer families called We Used to Own the Bronx. That book is currently being shopped around. “We’re actually very un-America in spirit,” she said. “Horatio Alger would not be welcome in our family. And the idea is to inherit your money and not make it—and the longer ago, the better.”

“I remember when my grandmother was still alive, the family would all go over to her house for a nice Christmas lunch,” said Ms. Biddle. “These days, it’s difficult to keep track of everyone.”