he following is from from Bert (The Pragmatic Romanticist):

. . .A lovely watercolour of Isabella Stewart Gardner portraying her at age 82, after her debilitating stroke in 1919. "Even I think it is exquisite", she wrote of it. It is quietly intimate. I like it. It's from the book I have about the Isabella Stewart Gardner Museum, a place that I adore.

Sargent had a great deal of affection for his sitter. She had been a huge supporter of his in Boston and commissioned a number of paintings. He also was quite sensitive to the plight of stroke victims. His own father had suffered from it before his died.