 Friend and confessor of Torquato Tasso.His madrigal texts were set by Monteverdi, Filippo Bonaffino, Orazio Vecchi, Luca Marenzio, Salamone Rossi, Pomponio Nenna and others.The close relationship between Grillo and Monteverdi appears in their correspondence, which began about 1610 and continued until the poet's death in 1629.