“There are two kinds of friends, and both mean very well,” she added. “One group doesn’t want you to grieve at all — ‘Come on, come on. It has been a week and a half since you lost Joe. Get out. Enough!’ The other kind never want to see you be anything but grieving. ‘Your husband is dead only eight years, and you’re wearing a red dress?’ ”

Joan Alexandra Molinsky was born in Brooklyn on June 8, 1933, to Meyer and Beatrice Grushman Molinsky, immigrants from Russia. Her father, a doctor, did comic impersonations of patients. Her mother insisted on piano lessons and private schools for Joan and her sister, Barbara, who grew up in Brooklyn and Larchmont. Joan attended Adelphi Academy in Brooklyn, Connecticut College for Women and Barnard College. A member of Phi Beta Kappa, she graduated in 1954 with a degree in English. Dreaming of an acting career, she worked in the publicity department at Lord & Taylor and was a fashion coordinator for the Bond clothing stores. Her marriage to James Sanger, the son of the Bond stores’ merchandiser, was annulled after six months in the 1950s. She married Mr. Rosenberg in 1965. Melissa was their only child. She survives Ms. Rivers along with a grandson, Cooper.

Her parents refused to support her acting ambitions, and she struggled for years as an office temp while taking small parts off Off Broadway. She went into stand-up to support her acting, working in grimy cafes and small clubs, and was fired often. But she liked comedy and was good at it. She developed fresh routines based on her experiences and observations, changed her name to Rivers and got a few breaks.

In “Seriously Funny: The Rebel Comedians of the 1950s and 1960s” (2003), Gerald Nachman wrote, “Rivers is actually the well-groomed comic granddaughter of Yiddishe mamas like Belle Barth and Pearl Williams, female titans who roamed the Catskills and Miami Beach and who reveled in subversive humor at the expense of both men and themselves.” He added, “When that wore out and she became a star, she turned her death ray on others, verbally abusing women who were thinner, richer and more famous while serving audiences as their new bitchy role model, styled by Oscar de la Yenta.”

There were risks and reversals in her more aggressive style. Her appearance on Jack Paar’s “Tonight Show” gave her national exposure, but audiences and Mr. Paar himself were appalled at her off-color ethnic jokes. Far from a springboard to success, it was a setback.