Margarett Williams Sargent (August 31, 1892-1978) was a painter in the Ashcan School; she exhibited as Margarett Sargent and as Margarett W. McKean.
Biography on Wikipedia: https://en.wikipedia.org/wiki/Margarett_Sargent
Woman in Striped Chair by Margarett Sargent
1932 / Oil on canvas / 28-3/8″x22-2/8″ / Collisart LLC, NY, NY
Margarett Sargent on Artnet: http://www.artnet.com/artists/margarett-w-sargent/