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LONDON - The discovery that his first child, Ivan, was severely disabled did much more than change the lifestyle of David Cameron. It also changed him as a person and a politician.
As political adviser to Cabinet ministers Norman Lamont and Michael Howard, and later as director of corporate affairs at Carlton Communications, Cameron's public school confidence sometimes extended to a touch of arrogance. Friends say that was knocked out of him by his and his wife Samantha's experience in bringing up Ivan.
At Carlton, former colleagues noticed a change after Ivan was born in 2002. One described him as a "different man" and "much less frivolous". Another said Ivan's disability had been "a real leveller".
Tory colleagues believe coping with Ivan's illness - and now his death - will give Cameron a "sense of perspective". That might make it easier for him to cope with setbacks and, one day, with Enoch Powell's dictum that "all political careers end in failure".
As one senior Tory official said: "David's priorities are very clear.
He is a family man first and foremost. His time as leader has been a roller-coaster. His personal experience has made him a more rounded figure, better able to remain calm and cope in a crisis. A disappointing opinion poll is not going to wreck his day."
Cameron has described the experience as "an eye-opener", saying: "Having a severely disabled son does bring you into contact with a lot of other elements of life.
"You do spend a lot of time in hospitals, you meet a lot of other parents and families in the same situation."
He and Samantha thought long and hard about whether he should talk publicly about Ivan. They decided he was such an important part of their lives that it would be wrong not to do so.
They knew they would face criticism. Prime Minister Gordon Brown, who takes a different view, said last year that politicians should not use their children as "props".
Cameron replied: "I am asking people a massive thing to make me their prime minister and they need to know a little bit about you, what makes you tick. I am the father of young kids - and my family is very important. All you can do in public life is what you feel comfortable with.
Some people criticise me for talking about Ivan but he is an important part of my life. My view is ... do what you feel comfortable with and let people judge."
Aides say that, because of his position in public life, Cameron can now speak on behalf of thousands of other parents with disabled children who would not otherwise have a voice.
- INDEPENDENT