However, mtDNA analysis has shown that the descendants of Brown Farewell's daughter Sister to Guy are maternally unrelated to descendants of branches 4-o and 4-p. These two branches are rather related to Families 11 and 13. There is therefore a pedigree error in Family 4, most likely in a GSB recorded descendant of Bay Layton not actually being related to her

Dam of [Old] Scar, winning racehorse 1710 to 1723; and of Chestnut Layton (by Makeless), from which branches 4-o and 4-p descend,

these branches including Kincsem (undefeated in 54 starts), Sir Harry (1798 Derby), St Patrick (1820 St Leger), Kate (1852 1000 Guineas), Gamos (1870 Oaks), Taj Mah (1929 1000 Guineas), Diolite (1930 2000 Guineas), Lavandin (1956 Derby), Pourparler (1964 1000 Guineas), Fleet (1967 1000 Guineas), Polygamy (1974 Oaks) and Camelot (2012 2000 Guineas and Derby)