The Mill Princess line was already established as something of a blue hen family by the time Coolmore made a further investment in it through the purchase of Beauty Is Truth in 2008.
As we know, very few of these powerful families pass the likes of Coolmore by. While built upon years of cultivation by Kilfrush Stud, then overseen by Brendan Hayes on behalf of former owners Jean-Pierre Binet and Richard Strauss, the operation and its associates had regular exposure to it over the decades starting with Mill Princess’ half-brother Assert, Robert Sangster’s wide-margin 1982 Irish Derby winner who was subsequently syndicated for $25 million to stand in the US.
Assert was part of a highly successful first crop for Be My Guest and not long after his outstanding three-year-old campaign, which also consisted of wins in the Prix du Jockey-Club and Benson & Hedges Gold Cup for David O’Brien, Coolmore added Assert’s relation Last Tycoon – the first named foal out of Mill Princess – to its roster. Billed (perhaps ambitiously) as the “most versatile horse in the world” in light of wins that ranged from the King’s Stand Stakes to Breeders’ Cup Mile, Last Tycoon’s male line today runs at its strongest through his son O’Reilly, a champion sire in New Zealand.
The family subsequently gifted Coolmore and its partners with Ice Queen, who was narrowly touched off in the 2008 Irish Oaks, while its sizeable 4.7 million guineas investment in Immortal Verse, a top miler in the colours of Strauss, is now bearing fruit following a quiet enough start.
However, perhaps more significant, as it turns out, was the private purchase of Beauty Is Truth. From a quick branch of the family, the Pivotal filly found her niche over five furlongs, the distance over which she bolted up in the 2007 Prix du Gros-Chene at Chantilly for Robert Collet.
Beauty Is Truth’s addition came just as Galileo was forging his reputation for clicking with quick mares. The mare’s first foal, Fire Fly, was a Dansili filly who was a multiple Group 3-winning sprinter for the Coolmore partners, but from then on, Beauty Is Truth was a regular partner for Galileo, with the visits yielding a pair of outstanding fillies in Hermosa and Hydrangea, the winners of four Group 1 races between them for Aidan O’Brien, as well as an Australian Group 1 winner in The United States.
Today, Hydrangea and Hermosa are doing plenty to drive this family forward. Hydrangea’s first two foals are the Dubawi pair Wingspan, a Listed winner last season who was second in her attempt to emulate her dam’s victory in the British Champions Fillies & Mares Stakes at Ascot, and this year’s Tetrarch Stakes winner Officer.
Hermosa, meanwhile, is dam of recent Hampton Court Palace Stakes winner Trinity College, another by Dubawi. He followed his Royal Ascot win with a close second to Leffard in the Grand Prix de Paris at Longchamp.
Whirl is out of a full-sister to Hydrangea and Hermosa who took nine tries to break her maiden
Yet the best of them, Whirl, is out of a full-sister to Hydrangea and Hermosa who took nine tries to break her maiden. The mare in question is Salsa, who gained her sole success for Aidan O’Brien when successful in blinkers in a mile maiden at Thurles. Whirl, a star of the current season whose Pretty Polly Stakes victory over Kalpana may turn out to be one of the defining moments of the season, is Salsa’s first foal.
As for Fire Fly, she has yet to produce a black-type horse but opportunities at that level will surely now come the way of her Ballydoyle-based two-year-old Kansas, a Wootton Bassett colt who put it together in first time cheekpieces to get off the mark at Tipperary in early July.
That’s to go with the work being done in another area of the family by the Coronation Stakes and Prix Jacques les Marois winner Immortal Verse. It took until her fourth foal, Tenebrism, for the mare to produce a stakes horse but that daughter of Caravaggio was a filly of the highest order on her day whose wins included the Cheveley Park Stakes and Prix Jean Prat. She was followed by the Justify filly Statuette, the unbeaten Balanchine Stakes winner whose career was cut short by injury, and now by the hardy miler Henri Matisse, this season’s Poule d’Essai des Poulains winner.
It is tempting to now regard this as a Coolmore family but in fairness, they would most likely be the first to give credit to Kilfrush Stud and its management under Brendan Hayes. So it’s very fitting that another of the clan’s current stakes winners, last December’s Tropical Park Oaks scorer See You Around, was bred by Hayes and races under his Cotton House Bloodstock banner. The Siyouni filly is out of Hayes’ Listed winner Besotted, a half-sister to the Group 1-winning miler Tie Black as well as the dam of this year’s John Of Gaunt Stakes winner Ten Bob Tony.
The exploits of Whirl, Henri Matisse, Trinity College, Officer, Ten Bob Tony and See You Around would suggest this family is in the midst of a purple patch. But this is one line that has been present at the top table with great consistency going as far back as the 1935-foaled Schiaparelli, dam of Lord Derby’s 1943 1,000 Guineas winner Herringbone.
Walter Haefner, then building up Moyglare Stud, bought into the family early on with the purchase of Irish Bird, by Sea Bird, for a record FR700,000 as a yearling at Deauville in August 1971 just weeks after the success of her half-brother Irish Ball in the Irish Derby. Several years later in 1978, Kilfrush followed suit, adding her Mill Reef half-sister Mill Princess for Ir£34,000 as a yearling in Ireland.
Fate dictated that while Moyglare moved Irish Bird on before she became a producer of note, Kilfrush held on to Mill Princess – albeit narrowly. By the time Irish Bird’s third foal Bikala won the 1981 Prix du Jockey-Club, the mare was in the hands of Captain Tim Rogers. A year later, it was the turn of her fourth foal, Assert, to follow suit during his brilliant season in 1982 that ultimately saw him ranked only a pound below Golden Fleece.
Meanwhile, Mill Princess had gone into training with Bernard Secly in France, for whom she had won at Longchamp. In a piece with myself for the Racing Post, Hayes recalled the mare that would come to underpin the fortunes of Kilfrush.
Mill Princess was actually earmarked for sale but then Assert won the French Derby
“Alain Decrion was our agent,” said Hayes. “He was a real pedigree buff and he liked the pedigree of Mill Princess. The filly wasn’t that nice – I remember she had a peculiar hind gait – but she had a page to die for. We bought her for Ir£34,000, put her into training with Bernard and she won at Longchamp.
“Mill Princess was actually earmarked for sale but then Assert won the French Derby. So we kept her, sent her to [Assert’s sire] Be My Guest and got [Group 2 winner] Astronef.”
At the time, Mill Princess’ first living foal Last Tycoon, by Try My Best, was a yearling. Astronef, another quick horse, was her third foal and subsequently followed by the Listed-placed Save Me The Waltz (by Kings Lake), dam of the 1999 Poule d’Essai des Pouliches heroine Valentine Waltz, and American Grade 1 winner Sense Of Style.

Last Tycoon wins the Breeders’ Cup Mile. Photo – George Selwyn
Mill Princess’s illustrious stud record also included Listed winner Side Of Paradise (by Sadler’s Wells), in turn the dam of Immortal Verse, Group 3 winner The Perfect Life (by Try My Best), Granddam of Ice Queen, and Tender Is Thenight (by Barathea), whose daughter Tie Black was awarded the 2006 Poule d’Essai des Pouliches.
The branch behind Beauty Is Truth descends from Mill Princess’ Caerleon daughter Zelda, a minor winner who foaled three smart sprinters for Strauss in the Prix Robert Papin winner Zipping, Prix du Petit Couvert winner Nipping and Prix du Bois winner Zelding. It is the latter filly, by Warning, who has done most to promote the line in recent years, not only as the dam of Beauty Is Truth but also Glorious Sight, a twice French Classic-placed filly for Haras de Saint Pair who is the dam of Group 2 winner Glycon.
Currently, there are 11 Group or Grade 1 winners within the Mill Princess clan. Kilfrush was sold by Jean-Pierre Binet in 2013 and its stock dispersed, but even before then, various operations had made an effort to buy into the family, Coolmore’s targeting of Beauty Is Truth and Immortal Verse being a case in point.
A likely aid in the growing prominence of Beauty Is Truth is her sire Pivotal, of course an exceptional broodmare sire. Beauty Is Truth was bred by Kilfrush in the year Pivotal’s fee jumped from £10,000 to £25,000, just as he was starting to gain major recognition from leading breeders. Immortal Verse followed four years later, by which time the Cheveley Park Stud stallion commanded £85,000.
It has been business as usual this year for his daughters, with eight stakes winners contributing to an European haul of approximately £3.6 million. Chief among those are Immortal Verse’s son Henri Matisse and Camille Pissarro, both of whom represent the Wootton Bassett cross.
Coolmore’s decision to invest so heavily in Wootton Bassett back in 2020 becomes more rewarding by the week. With his first Irish-sired crop still only three, he heads all European sires by prize-money (£4.8 million at the time of writing) and stakes winners (19).
Several of his early sire sons have also had a productive summer, in particular Haras de Bouquetot’s Wooded as the sire of Prix Jean Prat winner Woodshauna, something that won’t harm the growing legion of Ballydoyle-based potential stallion prospects when the time comes for them to go to stud.

Wootton Bassett: sire of Whirl and Henri Matisse. Photo – Coolmore

