At first glance, viewers see a familiar, reverently painted family scene. Yet the details in Mary Cassat’s “The Boating Party” hint at an underlying tension, as well as the strictures of late 19th-century society.

John Singer Sargent painted the well-known image of the young Homer Saint-Gaudens as an intimate portrait for his friend, the sculptor Augustus Saint-Gaudens, who was the boy’s father. In this and all his portraits of wealthy American youth, Sargent abandoned the sentimental approach of his contemporaries and painted them more naturalistically, with a keen, psychologically penetrating eye. In this image, he captures the impatience of the beautifully dressed young Homer with the boy’s expression and slumping pose.