Retired Household Cavalry horse Leonidas has died at The Horse Trust home of rest in Speen, Buckinghamshire.
“Leo” (pictured far right) was the final one of three former drum horses living at the charity to die.
He was preceded by Janus in September and Constantine on Boxing Day.
And The Horse Trust has also said goodbye to Thuglet, a 29-year-old Shetland pony who had lived at the sanctuary since 2007.
“We are very sad at the loss of Leo, particularly so soon after losing Janus and Constantine,” said Shirley Abbott, the yard manager at The Horse Trust.
“Leo was well-loved by staff and visitors to the sanctuary, and will be particularly missed by his groom Matt Bradley,”
27-year old Leo, a 17.2hh piebald gelding, worked at the Household Cavalry for 18 years.
His royal duties included guard duty in Whitehall, the daily Changing of the Guard, escorting The Queen and the royal family and participating in riding displays.
He had an impeccable service record, aside from one occasion where — during a Royal parade in Hyde Park — he left the ceremony to canter around the park, carrying his drums and musician with him.
Leo, who retired to the home in 2004, suffered a suspected heart attack on Friday (29 January).
Matt said, “Leo was an awesome character and all I can say he was my boy and I shall really miss him.”
Thuglet, a 36 inch bay Shetland gelding, arrived at the sanctuary from an animal rescue centre in Hertfordshire that closed down. He died on Thursday (28 January).
“Thuglet was a very cheeky character and will be remembered fondly by everyone who knew him,” said Ms Abbott.
“His personality certainly wasn’t proportional to his size — at times he acted more like a 16hh horse than a 36in Shetland pony.”