(CBS News) Queen Elizabeth II capped off her four-day Diamond Jubilee celebration without Prince Philip, her husband of 64 years.
Philip, the Duke of Edinburgh, remained in a London hospital on Tuesday after being diagnosed with a bladder infection.
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The British Monarchy hasn't released an official update on his condition, but Philip's youngest son, Prince Edward, Earl of Wessex, said his father was "feeling better," reports BBC News. While leaving the hospital, Edward told reporters that Philip probably just needs a "good rest." Edward said his father watched the Diamond Jubilee festivities on television.
In Philip's absence, the queen attended ae at St. Paul's Cathedral in London on Tuesday.
Rev. David Ison, the dean of St. Paul's, said Philip would be remembered in the prayers.
"We were already going to say prayers for the Duke of Edinburgh and it will have an added poignancy as we hope he will make a swift recovery," Ison said, according to the Associated Press.
, 90, to the hospital as a precautionary measure. He's expected to remain under observation for a few days.
There has been speculation that his illness could have been brought on or worsened after standing in the cold rain for more than four hours on Sunday as the royal family watched the flotilla sail down the Thames in London.
During Monday's star-studded Diamond Jubilee concert, Prince Charles told the crowd, "The only sad thing about this evening is that my father couldn't be here with us because unfortunately he's been taken unwell. If we shout loud enough, he might just hear us in the hospital."
Philip said he was "disappointed" to miss the festivities.