Bay City Roller is out of Bloomfield (Teofilo), a multiple stakes winner in Ireland whose wins include the Listed Vintage Tipple and the Listed Noblesse, from 1m4f to 1m6f, and who was twice placed at Group 3 level. She is also the dam of her only other winner so far, the triple winner Botanical (Lope De Vega), twice Listed-placed, including third in the Listed Doncaster Mile Stakes.

Second dam Ramona (Desert King) was unraced and has produced seven winners, among them Prima Luce (Galileo), winner of the Gr.3 Athasi Stakes and dam of Emmaus, a Listed winner placed at Group 2 level.

Third dam Rahaam (Secreto) was a winner and produced nine winners. They include the Group 1-placed sire Verglas (Highest Honor), winner of the Coventry Stakes, then a Group 3, the French Listed winner Persian Secret (Persian Heights), ancestress of Cross Counter, winner of the Gr.1 Melbourne Cup, and Cassandra Go (Indian Ridge), a dual Group 2 winner who won the King's Stand Stakes, then a Group 2, and was second in the Gr.1 July Cup. Cassandra Go's daughter Halfway To Heaven (Pivotal), a triple Group 1 winner, produced Rhododendron, winner of three Group 1 races, and Magical, winner of seven. Cassandra Go also produced the dual Group 3 winner Tickled Pink (Invincible Spirit), dam of Victoria Road, winner of the Grade 1 Breeders' Cup Juvenile Turf, and Theann (Rock Of Gibraltar), winner of the Gr.3 Summer Stakes and dam of Photo Call, a dual Grade 1 winner in the US, and of the sire Land Force, winner of the Gr.2 Richmond Stakes.

The family also includes Auguste Rodin (Deep Impact), winner of the Gr.1 Derby, a grandson of Halfway To Heaven.

Bloomfield has an unraced three-year-old filly, Blooming Rose (Blue Point), and a two-year-old colt, Rogue River (Blue Point).