Mary Stevenson Cassatt ( 1845 - 1926 ) was an American painter. Mary Stevenson Cassatt s works have been put up for auction numerous times, with realized prices surpassing estimated prices, varying from 1659500 USD for Sara seated, leaning on her left hand in 2002 to a remarkable record 6200000 USD for Children Playing with a Dog in 2007 , based on the size and medium of the artwork.