Sired by 2010 American champion 2-year-old male Uncle Mo, who has already sired 2016 Kentucky Derby winner Nyquist, Uncle Chuck descends from the family of Lady Be Good, a speedy daughter of Better Self who was a prolific producer for Wheatley Stable and Ogden Phipps after winning two stakes races as a juvenile but failing to train on. Given the status of a modern foundation mare by bloodstock expert John Sparkman, Lady Be Good produced four stakes winners and a slew of successful broodmares.
Impish, Lady Be Good's 1972 daughter by Majestic Prince, won her only start and became the dam of multiple Grade 2 winner Lay Down (by Spectacular Bid) and listed stakes winner Karly's Harley (by Harlan).She also foaled four daughters who produced stakes winners. The most notable of the group is I Pass (by Buckpasser), who won two of her three starts and was second in the other in her brief racing career. Bred to Mr. Prospector, she produced the brilliant but unsound Mining, whose six wins from seven starts included the 1988 Vosburgh Stakes (USA-G1).
Mining's older half sister Defer (by Damascus) never made it to the track at all but produced three multiple stakes producers in Cabaret Queen (by Gone West), Millie's Delight (by El Gran Senor) and Defer West (by Gone West). The last-named mare became a minor stakes winner as a 4-year-old but has been a better broodmare than runner, producing 2005 Honorable Miss Handicap (USA-G2) winner Forest Music (by Unbridled's Song) and 2000 Sapling Stakes (USA-G3) winner Shooter (by Dehere).
A very fast mare, Forest Music was also quite sound by the standards of her family, making 18 starts over three seasons of racing. As a broodmare, she has passed on a fair measure of her speed but not her soundness. Her first foal is Maclean's Music (by Distorted Humor), who won his only start and sired 2017 Preakness Stakes (USA-G1) winner Cloud Computing from his first crop. Her next foal to achieve some distinction is the Tiznow colt Kentuckian, whose three wins from 10 starts include the 2015 Lazaro Barrera Stakes (USA-G3). Electric Forest, Forest Music's 2015 filly by Curlin, won the 2019 Doubledogdare Stakes (USA-G3) but made only five starts over two seasons.
In Uncle Chuck, Forest Music has another runner who has shown brilliance, but the Los Alamitos Derby was only his second lifetime start, and Uncle Mo is better known for throwing speed than durability. Combined with a family that has had its share of soundness issues, the question of how long Uncle Chuck will last naturally arises. One hopes that it will be long enough to explore the full ability of a colt whose ancestress was good indeed.