Despite Pius VI 's lineage to a noble Cesena family , his only sister had married a man from the poor Onesti family .
Romualdo Braschi - Onesti , cardinal - nephew of Pius VI ( 1775 -- 1799 ) , was the penultimate cardinal - nephew .
Despite Pius VI 's lineage to a noble Cesena family , Romualdo Braschi - Onesti 's only sister had married a man from the cardinal - nephew Onesti family .
Romualdo Braschi - Onesti , cardinal - nephew of Pius VI ( 1775 -- 1799 ) , was the penultimate cardinal - nephew .