Leffard is out of the unraced Let's Misbehave (Montjeu) and is a half-brother to three winners, notably Sippinsoda (War Front), winner of the Listed Prix Occitanie, second in the Gr.3 Prix Chloé and fourth in the Prix Saint-Alary, then a Gr.1. Let's Misbehave is a three-parts-sister to High Chaparral (Sadler's Wells), winner of the Gr.1 Derby and twice of the Grade 1 Breeders' Cup Turf and later a sire of multiple Group 1 winners, and a half-sister to Black Bear Island (Sadler's Wells), winner of the Gr.2 Dante Stakes and second in the Secretariat Stakes, then a Grade 1, to the Listed-placed winners Treasure The Lady (Indian Ridge) and Helena Molony (Sadler's Wells), and to The Ethiopian (Sadler's Wells), a winner who was Group 1-placed over jumps.

The second dam is the unraced Kasora (Darshaan), a half-sister to two winners of the Listed 1,000 Guineas Trial, Kotama (Shahrastani) and Khanata (Riverman). Khanata was also placed in the Pretty Polly Stakes at the Curragh, then a Gr.2, and is the dam of Khatara (Green Desert), a winner who was placed in the Listed Brownstown Stud Stakes.

The third dam Kozana (Kris) won the Gr.2 Prix de Malleret and was twice placed at Group 1 level. She also produced Khoraz (The Minstrel), a five-time winner who was placed in several Group 1 races, and Korasoun (Darshaan), a winner and runner-up in the Listed Silver Stakes.

Let's Misbehave has a 2-year-old filly by Siyouni named Noble Honour and a yearling filly by Frankel.