Problem (牝 1823 栗毛 Merlin)
 |-- Nameless (牝 1831 栗毛 Emilius)
 |   `-- Mystery (牝 1842 鹿毛 Jerry)
 |       |-- Secret (牝 1853 黒鹿毛 Melbourne)
 |       `-- Tragedy (牝 1862 黒鹿毛 Glenmasson)
 |-- Namesake (牝 1832 鹿毛 Emilius)
 |   `-- Blameless (牝 1837 鹿毛 Reveller)
 |       `-- Griselda (牝 1856 鹿毛 Touchstone)
 `-- Io (牝 1836 栗毛 Taurus)
     `-- Sunflower (牝 1847 鹿毛 Bay Middleton)
         |-- Sunbeam (牝 1855 鹿毛 Chanticleer)
         |-- Chieftain's Daughter (牝 1859 栗毛 Lord of the Isles)
         |-- Mayflower (牝 1864 鹿毛 Thormanby)
         `-- Crocus (牝 1866 栗毛 Thormanby)