Emily Spicer reviews Michelangelo and Sebastiano at the National Gallery, London, on view through June 25, 2017.

Spicer writes: “For 25 years, give or take, Michelangelo and Sebastiano were close friends, a friendship apparently born from the former’s rivalry with Raphael. Michelangelo was godfather to one of Sebastiano’s children and when Sebastiano had a crisis of confidence, his confidant wrote to rally him (“Don’t say that you are not unique, when I write and tell you that you are …”). And this friendship bore some remarkable collaborations, remarkable because Michelangelo was not one for sharing the limelight. He drew studies and designs for his friend’s commissions and was, in turn, influenced by the subject matter of Sebastiano’s paintings.”