Kind Of Blue is one of two winners out of the unraced Blues Sister (Compton Place), the other being Bluebird (Acclamation), who won over 5f at Southwell. Blues Sister is a full sister to Deacon Blues, who won the British Champions Sprint Stakes, then a Group 2, in 2011, and a half-sister to Holley Shiftwell (Bahamian Bounty), twice placed at stakes level. Blues Sister is also a half-sister to The Tin Man (Equiano), who won the same race in 2016 as well as the Gr.1 Diamond Jubilee Stakes and the Gr.1 Haydock Sprint Cup.

Second dam Persario (Bishop Of Cashel) won twice and has nine winners besides Blues Sister, headed by The Tin Man and Holley Shiftwell. She is a half-sister to Warningford (Warning), runner-up in the Gr.1 Lockinge Stakes, three times a winner of the Gr.3 Leicestershire Stakes and later a sire.

Third dam Barford Lady (Stanford) won twice and is the dam of Warningford. She and the Listed winner Ansellman (Absalom) are out of the same mare.

Blues Sister's two-year-old is a gelding by Starspangledbanner called Blue Anthem; she visited Sioux Nation in 2023.