Britain's Prince Philip spent a third night in the hospital as he recovers after treatment for a blocked coronary artery.
The 90-year-old husband of Queen Elizabeth II is in good spirits and will remain under observation for "a short period," Buckingham Palace officials said Monday. There are no details of when he may be released.
The prince underwent a successful coronary stent procedure at Papworth, a specialist heart hospital in Cambridgeshire, where he was taken on Friday after complaining of chest pains.
It was the most serious health scare suffered by Philip, who is known to be active and robust. He has continued to appear at many engagements, most recently taking a 10-day tour of Australia with the queen.
He is likely to miss the Royal Family's traditional Boxing Day shooting party on Monday at the queen's private Sandringham estate in Norfolk, an event he usually leads.
Six of Philip's grandchildren, including Princes William and Harry, visited him Sunday in the hospital.