Spirit Son - winner of the 2011 John Smith's Mersey Novices' Hurdle at Aintree - has died at his retirement home, the Greatwood charity at Marlborough.

After missing the Cheltenham Festival in 2012 due to a tendon problem, Spirit Son, then a six-year-old in training with Nicky Henderson, was recovering at Charlie and Tracy Vigors' Hillwood Stud near Marlborough, where he was found on the floor of his box unable to get to his feet.

Tests showed he had a rare virus that attacks the neurological system but which can remain dormant.

A scan later revealed a neck fracture, which was operated on, but led to Spirit Son's retirement from racing.

Owned by Michael Buckley, Spirit Son had been cared for by the Greatwood charity at Rainscombe Hill Farm, Clench Common.

In a statement Greatwood said today: "It is with great sadness that Greatwood charity has to report that Spirit Son deteriorated over the summer to such an extent that he had to be put to sleep this morning.

"Our thoughts go out to all his connections."

Sasha Thorbek-Hooper, fundraising and marketing manager for the charity, said today: "It has been really upsetting for the team, especially as he was such a gentle soul."

Mr Henderson said in 2012: "It has been a traumatic time for everyone and Spirit Son has been incredibly brave.

"It has been a fantastic team effort to save the horse, from Michael [Buckley], who cares so deeply about all of his horses, to the various teams of vets and everyone here at Seven Barrows and at Hillwood.

"The prognosis for Spirit Son racing again remains very low, but he deserved a chance to have a life, whether it is on a racecourse or in another role."

Established in 1993, Greatwood is the longest standing racehorse welfare charity in the UK and the only organisation that uses ex-racehorses to educate disadvantaged children and young adults with special educational needs.

Further information at www.greatwoodcharity.org