Carolina Mandorff (1799-1874), married Wester as a child Per Krafft the Younger (1863-1777)

The picture has something of this: people, portrait, girl, wear, child, woman, facial expression, son, indoors, nude, model, room, music, dress, fashion, baby, hairdo.
Perhaps it’s a painting of a young boy sitting on a chair with his hands on his knees and his chin resting on his hand resting on the back of the chair.