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The Jester Calabacillas is a portrait by Velázquez of Don Juan Martín Martín, "Juan de Calabazas" or "El Búfón Calabacillas", a jester at the court of Philip IV of Spain, sometimes known by the nickname Bizco. It is now in the Prado Museum. The jester had mental illness(s), and would often rub his hands together in a form of tic; however, Velazquez painted him in a relatively calm state, further showing Velazquez's equal show of dignity to all, whether king or jester.