Heart of Joy, a foal of 1987, is a daughter of Lypheor out of the Secretariat mare Mythographer. Heart of Joy won the Nell Gwyn Stakes (Eng-III) and ran second in both the classic One Thousand Guineas Stakes (Eng-I) and Irish One Thousand Guineas (Ire-I).

Trained by Gary Jones in the United States, she won the Palomar Handicap (gr. IIT), San Simeon Handicap (gr. IIIT), and Las Cienegas Breeders' Cup Handicap (gr. IIIT). She also ran second in the Ramona Handicap (gr. IT).

Heart of Joy earned $733,755 racing for Mr. and Mrs. John C. Mabee's Golden Eagle Farm. She was bred in Florida by Tartan Farms.

As a broodmare, her first foal, Meiner Love, was her best runner on the track. Meiner Love was a multiple stakes winner in Japan and earned more than $2.6 million.