Tappan Street is out of the graded-placed Virginia Key (Distorted Humor), third in the Grade 2 Gazelle Stakes, and is her first stakes winner and second black-type horse after the Listed-placed Distorted D'Oro (Medaglia D'Oro). Virginia Key is a half-sister to the Grade 1 winner Grace Adler (Curlin), the graded winner Pyrenees (Into Mischief) and the dam of Miuccia (Mitole), a stakes winner and graded-placed.

Second dam Our Khrysty (Newfoundland) was a graded winner who won six races, among them the Grade 3 Turnback the Alarm Handicap at Belmont. Her six winners are headed by Grace Adler, winner of the Grade 1 Del Mar Debutante Stakes, and Pyrenees, winner of the Grade 3 Pimlico Special Stakes, and she is the grandam of the Listed winner Miuccia.

Third dam The Hess Express (Lord Carson) was Listed-placed and has nine winners. They include the sire Bullsbay (Tiznow), winner of the Grade 1 Whitney Handicap, the Listed winner and sire Vegas No Show (Hard Spun) and the Listed winner Hidden Expression (Yonaguska), dam of Mask, winner of the Listed Mucho Macho Man Stakes. She is also the grandam of the Listed-placed Fearless Soldier (City Of Light).

Virginia Key has a 2-year-old colt by Curlin named Weekend Glory and a yearling filly by Quality Road, and she was bred to Cody's Wish last year.