From Museum of Fine Arts Boston:
Stéphanie Primicile Carafa, Marchesa di Cicerale and Duchessa di Montejasi, was the sister of Degas’s father. Their father, a Frenchman who fled to Naples during the French Revolution, eventually established a banking house there. This is the last of Degas’s great family portraits. It is also among the most surprising. The portrayal of the artist’s Aunt Fanny is without flattery, delicately balanced between austerity and empathy. Her frontal, static, focused image is contrasted with the lively bearing of her daughters, whose sense of movement is increased by the offhand way in which the artist painted, then wiped away, their portraits.