Anxious to explore, Janet was tired of the "superficial social life of her world in New York," and, in 1918, at age 24, she joined the Red Cross as a nurse in France to help out the war effort and to be near her fiancé, Frederick Roelker Wulsin, whom she married in 1919.

[2] Janet served as a Red Cross nurse in the French Third Republic during World War I.

In 1919, she left New York for Paris, where she married Frederick Wulsin, a Harvard University graduate from a self-proclaimed prominent Ohio family.

From 1921 to 1925, the couple mounted expeditions to the far reaches of China, Tibet, and Outer Mongolia to study the people, flora, and fauna of the region.

Janet's role in her first husband's expeditions went largely uncredited until after her death in 1963, when her daughter, Mabel Cabot, mother of Ali Wentworth, found her mother's private letters and diaries and published Vanished Kingdoms (ISBN 1-931788-08-1), a biographical account of Janet's explorations.