The pair arrived by taxi at 3.45pm and rushed inside without saying anything for reporters. But Pippa, dressed in a brown belted coat and suede boots, smiled widely at one point, suggesting that her sister's condition may be improving.
James, who has grown a beard, carried a bag of what appeared to be magazines, no doubt a present for Kate to keep her entertained during her hospital stay. The 25-year-old and Pippa stayed for more than an hour, leaving at 5pm. Their visit was followed by one from Kate's mum Carole, who arrived at 7.30pm.
Prince William was back again to see his wife for the third day running. The Duke, dressed casually in beige trousers and a blue jumper, spent five hours by her side, going home at around 5pm. He declined to answer questions from the press waiting outside the King Edward VII hospital, where Kate was admitted on Monday.
The Prince is said to be upset at an intrusion to Kate's privacy, which happened in the early hours of Wednesday morning. Two presenters who phoned the hospital pretending to be the Queen and Prince Charles managed to obtain intimate medical information about the expectant royal, who is suffering from servere morning sickness.
Believing them to be genuine, the nurse who answered the call at King Edward VII Hospital told them Kate had had "a comfortable night" and revealed private medical information.
A hospital spokesman said: "This call was transferred through to a ward and a short conversation was held with one of the nursing staff. King Edward VII's Hospital deeply regrets this incident."
John Lofthouse, the hospital's chief executive, said: "This was a foolish prank call that we all deplore."
In a statement, 2Day FM – the radio station behind the hoax - said they "sincerely apologise for any inconvenience caused by the inquiry... The radio segment was done with the best intentions, we're glad to hear Kate is doing well and we wish her all the best."
The presenters behind the prank, Mel Grieg and Michael Christian (above), said: "We were very surprised that our call was put through, we thought we'd be hung up on as soon as they heard our terrible accents. We're very sorry if we've caused any issues and we're glad to hear that Kate is doing well."
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