Michael Haydn was his younger brother, once as well known. Haydn was Porpora’s accompanist and valet whilst learning “the true fundamentals of composition” from him. He didn’t really get on with his pupil Beethoven; Hummel and Mozart also studied with him. He told Leopold Mozart that his son (who later joined Haydn’s Masonic lodge) was “the greatest composer known to me.” He met Martin y Soler, Cherubini and Kraus (who dedicated a symphony) in Vienna, and his friends Clementi and Reynolds (who painted him) when living in London. The last time he heard his own music performed, Salieri directed.