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Charles Willson Peale, Staircase Group (Portrait of Raphaelle Peale and Titian Ramsay Peale), 1795, oil on canvas, 89-1/2 x 39-3/8 inches / 227.3 x 100 cm (Philadelphia Museum of Art).

View this work up close on the Google Art Project: http://www.googleartproject.com/collection/philadelphia-museum-of-art/ar...