WILLIAMSTOWN — In one biography of Georgia O’Keeffe, the famed artist’s four sisters are mentioned only in passing, as though her family was incidental to her success as an artist.

In the novel “Georgia,” by Dawn Tripp, the sisters only dabble in art. Catherine is a fulfilled mother, Claudia a teacher, Anita a society wife, and Ida a full-time nurse.

In fact, both Catherine and Ida showed artistic talent, but Georgia pressured them to stop painting and exhibiting their work. Catherine eventually retreated into marriage and motherhood, but Ida would not be cowed. An estrangement resulted.

Selections from this younger sister’s work are now on display at the Clark Art Institute, in Williamstown. “Ida O’Keeffe: Escaping Georgia’s Shadow” is a provocative look at Ida Ten Eyck O’Keeffe’s decades of experimentation in abstract and realistic forms.

Both Catherine and Ida exhibited in New York in the 1930s. Mrs. John D. Rockefeller bought Ida’s monotype “Mount Washington” in 1934, and The New York Times called her 1940 exhibit “unquestionably her most striking accomplishments to date.”

But lacking a patron, Ida had to cobble together a living. At one point in the 1930s, she wrote and illustrated a school guidebook on Native Americans. Temporary teaching appointments took her across the country, where each address provided new inspiration: a night sky in Texas, a banana tree in California.

She died after a stroke in 1961, at age 71; Georgia outlived her by 25 years.

The finest example of Ida’s work in this exhibit is a series of paintings of Highland Light, in North Truro, which grow increasingly abstract as the beacon’s rays move from orbs to triangles and a seagull’s wings appear and disappear.

This sort of experimentation can be admired, but the fact that she did not settle on a particular style hampered her commercial potential. Some of her paintings vanished after her death. There seemed to be no end of bad luck for Georgia O’Keeffe’s younger sister.

It’s tempting to wonder what Ida O’Keeffe could have accomplished with a powerful patron like her sister’s husband, the gallery owner and photographer Alfred Stieglitz, or with enough money to avoid the grind of college teaching. But wandering through this exhibit, one wonders if the lesson is not Ida’s struggles, but our definition of success.

The word success is from the Latin sub plus cedere, “to go along.” Its original meaning, “to go under, to go up, to follow,” implies “succession,” rather than our contemporary definition of success, which is to achieve and be recognized, often through wealth or fame.

Ida O’Keeffe did go her own way, in spite of her sister. Sometimes she moved under Georgia’s shadow, but she also rose above it, by refusing to give up her art to satisfy Georgia’s misguided sense that her own work might be compromised by her sister’s.

The famous O’Keeffe’s actions might have arisen from insecurity, if we are charitable, or from egotistical selfishness, if we are not. In any case, she did a grave disservice to Ida and all the people who might have enjoyed her work.

This exhibit of 35 paintings, prints and photographs was organized by the Dallas Museum of Art, where it was shown from November 2018 to February of this year.

Here, it has been sidelined in Clark’s research library, rather than the main exhibit hall, which is showing “Renoir: The Body, the Senses,” a collection of his nudes. But the Clark has extended the Ida O’Keeffe show to Oct. 14 because of demand, and Ida’s works are getting as much attention as the French master’s.

The New York Times art critic Roberta Smith wrote in her review that Ida “had a way with paint that Georgia either lacked or suppressed,” and Art New England devoted a three-page spread to the exhibit, describing some of the paintings as “undeniably powerful.”

Yes, it’s a shame that Ida had such a difficult time of it. Her oeuvre is not as extensive or cohesive as Georgia O’Keeffe’s desert and flower paintings, and she never made the millions her sister did.

But Ida O’Keeffe made art her life and pursued inspiration where she found it. She, too, was an artist, one worthy of an exhibit at the Clark, one of New England’s finest museums. Her work invites us to appreciate her talents on her own terms, not in comparison to her famous sister — and to rethink our definition of success.