Politics for breakfast: Will Cameron regret placing tots in the frontline?

Are Shreddies "green"? Was the milk organic? Does Samantha really look that good first thing in the morning? These questions and more were raised by the decision of the Conservative Party leader David Cameron to allow television cameras into his home last week and film his whole family having breakfast. Not just Dave, who has chosen to become a public figure, but his previously less public wife and the children, Ivan, 6, Nancy, 4, and two-year-old Elwen, who presumably have no say in the matter.

The footage broadcast by ITV on Thursday night showed Mr Cameron spooning cereal into Elwen's mouth, pouring it out for Nancy and rolling around on the sofa with them both. He held his eldest son, who has severe epilepsy and cerebral palsy, and said: "Oh, you've woken up. Good morning, Ivan." Touching scenes, no doubt similar to those in many a wealthy, posh, extremely well-organised North Kensington home.

And why were we seeing them? Because Mr Cameron wished to promote a series of new family-friendly policies. "People want to know who you are and what you are like and what makes you tick," he said, justifying this self-intrusion. "That's modern politics. You just have to do what you feel comfortable with."

Gordon Brown wouldn't feel comfortable with any of it. Both as a politician and a man he seems to have benefited enormously from having a wife and two children – although there has been suffering too, in the death of their first-born, Jennifer. Mr Brown has a son with cystic fibrosis but he has never allowed his family to be filmed or photographed, except for official portraits.

So what should we make of Mr Cameron's display of domestic harmony? I have been to breakfast at the Cameron home, albeit uninvited, and can vouch for the authenticity of the TV portrayal of him as a man at ease with his kids. Nancy padded downstairs, into the open-plan kitchen that was flooded with light from the garden thanks to an entirely glass wall, and she made straight for her dad's lap. Only men who know how to handle a baby can be as relaxed as he was in feeding Elwen from a bottle, despite already being dressed for political action in a French blue shirt.

It was just after seven in the morning, and I had arrived far too early at their Edwardian terraced home for our scheduled interview, but an unflustered Mr Cameron let me in and made coffee. Samantha's party shoes were on their sides on a white rug on the floor. Ivan was in the basement, where the Camerons have built special accommodation for him and the full-time carer he requires. "Ivan is so much part of the family that he would have to be there," said an aide of the television scenes.

Ivan's condition would be a massive challenge to any parent. Being open about it has sometimes been politically useful though. A year ago, when pushing his green credentials hard, it emerged that Mr Cameron had taken a private jet from Oxford to Hereford. But he dampened the criticism by revealing that the flight had been provided by a friend who was designing a new wheelchair for Ivan.

Sometimes the tactic backfires on him. Presenting himself as a friend of the NHS, Mr Cameron praised the ambulance drivers who took Ivan to his day care centre. When it closed he held a party for fellow users and staff, including the drivers Jack and Doreen Ingrams. But they were left unhappy. "I think he was almost embarrassed by us being there," said Mr Ingrams, who felt "shovelled out" after a drink and sandwiches while posher couples were invited for dinner.

Whether to involve your kids in your political day job becomes a much more difficult question when they stop being cute and turn into snarling teenagers, as Tony Blair found when his boy Euan was found drunk in Trafalgar Square. If you take the Cameronian approach, what happens if you get to No 10 and your vulnerable pubescent son or daughter harms him or herself or does something illegal? It might be too late to bring down the veil then.

As for the answers to those questions, Nestlé, who make Shreddies (and are boycotted by many people for their baby milk policies) say they have plans to improve their performance on waste, recycling and energy use. But no, the cereal is not paricularly environmentally virtuous. Samantha, I can report, looks as horrified first thing in the morning as any woman would if they came down unmade-up to find a stranger in the kitchen. And the milk? In this respect, at least, there is still some mystery in politics.