Giuliano da Sangallo was an architect along with his father, uncles and his son. Giuliano commissioned these portraits soon after his father’s death. A death mask was probably used to recreate his father’s likeness. This diptych is an early example of a portrait in which the subject’s profession plays a key role. On the table in front of each subject lies the tools of their profession. Giuliano got a pen and dividers for architecture, but Francesco, who was not only an architect but more importantly a musician, got a piece of sheet music. Giuliano was a part of the Renaissance scene. He assisted in the design of St Peter’s Basilica. He was also called upon to help Michelangelo remove mold from the Sistine Chapel ceiling after the younger artist had applied too wet a plaster. Originally Piero di Lorenzo, Cosimo took the name of his master Cosimo Rosselli. He also took his daughter in marriage, and assisted him in his Sistine Chapel frescos. During his lifetime, Piero acquired a reputation for eccentricity. Reportedly, he was deathly afraid of thunderstorms, and so pyrophobic that the only food he cooked was hard-boiled eggs, which he prepared 50 at a time while boiling glue for his artworks. The great historian Vasari wrote, “Through his brutish ways he was rather held to be a madman. He could not stand babies crying, men coughing, bells ringing, or friars chanting,”  See original: https://www.rijksmuseum.nl/en/collection/SK-C-1367