Her dam, Monsoon finished second in the wartime substitute Oaks in 1943 and was bought by Dewar as a prospective broodmare for 7,300 guineas at the end of her racing career.
As a descendant of the broodmare Rose Red, Monsoon came from the same branch of Thoroughbred "Family" 1-w which later produced Celtic Ash, Larkspur, Altesse Royale and Nocturnal Spree.
[8] On her next appearance, Festoon ran in the ten furlong Druid's Plate at her home course of Salisbury and was beaten by Valerullah, a colt to whom she was attempting to concede sixteen pounds.
The win led some observers to conclude that Festoon had stamina limitations, especially as Fair Trial's progeny seldom excelled at distances beyond nine furlongs.
Ridden by Joe Mercer, who took over the ride after Breasley was badly injured in a fall in a race at Alexandra Park,[10] she finished fifth to the French-trained filly Sun Cap, apparently failing to stay the distance.
As a broodmare she produced five winners, two of which were close to top class: Pindaric[15] (sired by Pinza), won the Lingfield Derby Trial in 1962, while Atilla (sic),[16] by Alcide, was a successful international performer whose wins included the Gran Premio del Jockey Club and the Grosser Preis von Baden.