Jacqueline O'Brien is married to Vincent O'Brien and lived in Ireland at Ballydoyle for over fifty years. She is an honours graduate of the University of Western Australia and the Open University, co-author and photographer of Great Irish Houses and Castles and Dublin, a Grand Tour, and photographer of Ancient Ireland. She is co-author of Vincent O'Brien's Great Horses. All her four books were number one bestsellers.
Ivor Herbert has written twenty-three books, of which fourteen have been about horses and racing, including the continuing bestsellers Red Rum and Arkle. He trained racehorses himself, with some success, winning the Gold Cup in 1957, the youngest Englishman to do so since the Second World War (though Vincent was younger by a year when Cottage Rake won in 1948). Ivor has been a friend of the O'Brien family for over thirty years.