John Gretton, 3rd Baron Gretton British baron (1941–1989) Parents John Gretton, 2nd Baron Gretton Anna Helena Margaret Loeffler Children Sarah Margaret Gretton John Gretton, 4th Baron Gretton Siblings Anthony David Erik Gretton Mary Ann Maud Sigrid Gretton Elizabeth Margaret Gretton Partners Jennifer Gretton, Baroness Gretton