|Vincent? Theo? Theo.|
While the world knows of the many letters written by Vincent van Gogh to his brother Theo, it was believed that the artist never painted a portrait of his brother.
Van Gogh painted several self-portraits and now one of these formerly considered a self-portrait is being considered as actually a portrait of Theo. Close comparison of photos of Theo and this particular portrait have led researchers at the Van Gogh Museum in Amsterdam to this conclusion.
More about the finding here.