The Mellon family has maintained a home at Mill Reef since its founding in 1947.
In a very successful stud career his offspring included Shirley Heights, Acamas, Wassl, Diamond Shoal, Fairy Footsteps, Doyoun, Glint of Gold, Ibn Bey, Lashkari, Milligram and Reference Point.
Mill Reef died in 1986 and he is buried within the National Stud where a statue stands in his memory. The Mill Reef Stakes at Newbury is named in his honour. Remember me, all men who love the Horse, If hearts and spirits flag in after days; Though small, I gave my all. From Paul Mellon's speech at the Gimcrack Dinner 1970.
During a routine training gallop, however, he stumbled and shattered his foreleg.
Charles Allen, a veterinary specialist, was flown in. A triangularly shaped piece of bone about two and a half inches long was broken from the lower end of the cannon bone and was considerably displaced.
The inner sesamoid bone was completely shattered, and the rim of the top of the main pastern bone was damaged.
It seemed likely that the inner sesamoid bone was the first to break, with the result on the next step that the fetlock was not braced and the foot and the pastern were pointing outwards.
The sheer pressure of the horse's weight caused the crumbling of the rim of the pastern bone and the breaking of the cannon bone.
It was decided that an operation would be performed in a building in Ian Balding's yard.
Back on home soil, he was entered in the Gimcrack Stakes at York in mid August.
After a torrential overnight downpour turned the going into a quagmire, his trainer wanted to scratch him from the race.
Mill Reef won twelve of his fourteen races and finished second in the other two.