The Ruth Westheimer that fellow residents of her Manhattan apartment building knew was much the same person known to America as Dr. Ruth: gregarious, funny, peppy and apt to throw out a provocative question in the elevator.

“She was the most well-loved person who lived here,” said Geoffrey Katin, 81, a longtime resident of the building, in Washington Heights.

Dr. Westheimer, who died on Friday at 96, was America’s best-known sex therapist. She first shocked and amused millions in the 1980s with her frank radio counseling sessions and later became a hit on national talk shows, wrote many books, gave lectures and was the subject of a play and a documentary. But her explicit and direct advice, delivered in a casual and jovial manner, was not just for the cameras.

Neighbors enjoyed bumping into her in the building, never certain how she might strike up a conversation. Peter Sparrow, who said he had lived there for 27 years, recalled the time Dr. Westheimer, who was 4-foot-7, asked four burly construction workers in the elevator if they performed a specific sex act on their wives.

“This little woman just quizzing these men about their sex lives,” he said. “It probably helped them.”

Dr. Westheimer’s popularity peaked in the 1980s, but she remained active into the 2020s. She had recently turned her attention to a new challenge: the epidemic of loneliness. Last year she pitched herself to Gov. Kathy Hochul of New York as the state’s first “loneliness ambassador,” having experienced firsthand the isolating effects of lockdowns during the coronavirus pandemic. The governor took her up on the offer.