David Cameron`s Disabled Son Dies Aged 6

Cameron and his wife Samantha have two other children, Nancy, 5, and Arthur, 3.

Conservative Leader David Cameron's disabled six-year-old son Ivan has died after being taken ill overnight, prompting a political truce as party leaders expressed their sympathies.

Ivan, who suffered from cerebral palsy and severe epilepsy and needed constant care, died at 6:30 a.m. on Wednesday at St Mary's Hospital, Paddington, a hospital spokesman said.

Proceedings in parliament were suspended as a mark of respect.

Prime Minister Gordon Brown, whose infant daughter Jennifer Jane died from a brain haemorrhage in 2002, spoke of the "unbearable sorrow" of a child's death.

Party leaders agreed to suspend the week's normally fractious Prime Minister's Questions session where Brown and Cameron would have been trading political barbs.

A visit of Margaret Thatcher to 10 Downing Street for the unveiling of a new portrait of the former Conservative leader was also cancelled.

"Every child is precious and irreplaceable and the death of a child is an unbearable sorrow that no parent should ever have to endure," Brown told the House of Commons.

"Politics can sometimes divide us. But there is a common human bond that unites us in sympathy and compassion at times of trial and in support for each other at times of grief."

Conservative foreign affairs spokesman William Hague told MPs that Ivan Cameron's six years of life "were not easy ones."

"Ivan their son suffered much in his short life but he brought joy and love to those around him. As David himself has said in the past, for him and Samantha he will always be their beautiful boy."

Cameron and his wife Samantha have two other children, Nancy, 5, and Arthur, 3.

"David and Samantha would ask that their privacy is respected at this terribly difficult time," they said in a statement.

Cameron's experience of caring for Ivan has been seen as the driving force behind his promotion of "Compassionate Conservatism", helping make the party electable again after a decade in the political wilderness.

The party is ahead in opinion polls with the most recent surveys predicting the Conservatives would be returned to government if an election were held now.

Before Cameron was elected leader in December 2005, the Conservatives had struggled to shake off their image of being, in the words of one-time chairman Theresa May, the "nasty party".

Cameron has made a priority of defending the state-funded National Health Service, praising it for all the help it had given his elder son.

"When your family relies on the NHS all the time -- day after day, night after night -- you know how precious it is," he said.