HARTFORD, Conn. — Sada Thompson, the durable matriarch of stage and screen who won a Tony Award for her portraits of three sisters and their mother in the 1971 comedy “Twigs” and an Emmy Award for playing the eternally understanding mother in the television series “Family,” has died at age 81.

Thompson died Wednesday of a lung disease at Danbury Hospital, agent David Shaul said Sunday from Los Angeles.

Thompson won wide acclaim during an illustrious career that spanned more than 60 years, during which she gravitated toward quality work that allowed her to plumb her characters’ complexities.

“When you start off acting, it does seem very romantic, and the make-believe part of it all seems very exciting,” she told the Los Angeles Times in 1991. “It’s only later that you begin to realize how fascinating the work is — that it’s a bottomless pit, and you never get to the end of it. Human character is just endlessly fascinating.”

Even before she graduated in 1949 from Pittsburgh’s Carnegie Mellon University, then called the Carnegie Institute of Technology, she was on a trajectory to take on challenging roles drawn from the classics as well as contemporary plays.

A prolific actress, she made her mark in theater and film generally portraying the matriarchs in family dramas.

In her stage debut in 1945, she played Nick’s Ma in William Saroyan’s “The Time of Your Life.” She also played the slovenly and bitter mother, Beatrice, in the 1965 production of “The Effect Of Gamma Rays on Man-in-the-Moon Marigolds” and Dorine in “Tartuffe” (1965). She collected Obies for the latter two.

By far, her biggest Broadway success was “Twigs,” by George Furth, in which she played three sisters — as well as their mother. She won a Tony and the New York Drama Critics Award that season.