At the height of her fame and success , she scandalized the world , when she began an affair with Italian director Roberto Rossellini , while still married to her first husband Dr. Peter LindstrÃ m. She and Rossellini were eventually married in 1950 . During production , Bergman fell in love with Rossellini , and they began an affair . Bergman became pregnant with Rossellini 's son , Renato Roberto Giusto Giuseppe ( `` Robin '' ) Rossellini ( born 2 February 1950 ) .