Nancy Ludlow Tuckerman was born on Oct. 24, 1928, in Manhattan. Her father, Roger, was a stockbroker, and her mother, Betty Thompson Tuckerman, was an event planner.

She said she first met Jacqueline Bouvier at 8 or 9 when both were students at the Chapin School in Manhattan. Later they were roommates at Miss Porter’s School, a college preparatory school in Farmington, Conn., where young Jackie tried with only limited success to teach her to ride a horse. Next to Jackie’s 1947 yearbook photo, it says that she can generally be found “laughing with Tucky,” Ms. Tuckerman’s nickname.

Ms. Tuckerman had been a travel agent in New York City for about 10 years when her old friend, now the first lady, asked her to become her social secretary, taking over the job from Letitia Baldrige. “‘Tuck’ Replaces ‘Tish’ on Mrs. Kennedy’s Staff,” read a headline in The Times over a United Press International article announcing the news.

“Miss Tuckerman is attractive with golden brown hair, blue eyes and a comely five foot five figure,” the article said, a sentence indicative of the tenor of the day.

Reporters may have viewed the social secretary’s job with a certain condescension, but it required serious organizational skills, since Mrs. Kennedy was proving to be a popular first lady and the focus of countless requests.

“I think we received about 800 letters a day,” Ms. Tuckerman said in the oral history.

She also supervised other staff members and organized dinners and other White House functions. She took over the job just as the busy spring season was ending and Mrs. Kennedy’s pregnancy was leading her to reduce activities. But in early September 1963 she had her first chance to stage a major event, a dinner for the king and queen of Afghanistan.