The collective noun for O'Callaghans is unknown, but at bloodstock sales around the world they can often be found travelling as a pack. An intimidating force perhaps, the Yeomanstown O'Callaghans--not to be confused with their cousins, the equally successful Tally-Ho ones--are a close-knit clan who have made a prosperous business of breeding and trading horses with a little help from sire sensation Dark Angel (Ire). Away from the sales, though, the brothers are scattered around Ireland and, at Grangemore Stud, Guy O'Callaghan is quite clearly doing his own thing. "It's...