The Duke of Edinburgh will find out today whether he will be forced to spend his 91st birthday in hospital.
The Duke was admitted to the King Edward VII Hospital in central London on Monday suffering from a bladder infection.
Yesterday, he enjoyed the company of grandsons the Duke of Cambridge and Prince Harry who paid a short, private visit.The Princes, dressed in jeans and V-neck jumpers, left the hospital after 20 minutes without commenting.
Philip has already been visited by the Queen, the Duke of York, the Earl and Countess of Wessex and their children.
Andrew said on Wednesday his father was "mending very well" but Buckingham Palace said they had no further update on his condition and did not know when he would be discharged.
Philip had been planning to celebrate his birthday on Sunday privately and is not due to attend his next scheduled engagement until Tuesday, when the Queen hosts a garden party at the Sandringham Estate to mark her Diamond Jubilee.
It is hoped her husband will be by her side at her Norfolk retreat if he has been discharged in time.It is also hoped he will be able to accompany her to the East Midlands on Wednesday for a two-day visit as part of the Queen's Jubilee tour of the UK.
Philip's admission to hospital meant he was forced to miss some of the Jubilee celebrations this week.He spent Sunday braving the elements for the Thames River Pageant, which doctors suggested might have exacerbated his condition if he did not make enough visits to the toilet.
The Palace said earlier this week that he was being treated with antibiotics and was in good spirits.