IAM currently reading, (or should I say consuming?) Madonna's brother's book. It had been touted as a horribly salacious tale containing absolutely hideous things you didn't know about Madonna.

Me being such a nice, high-minded individual, I called the publicist and begged to be sent an advance copy of Life with My Sister Madonna, but had to wait and buy one in a bookshop, like everyone else. So when I finally got my hands on one, it was exactly like being a kid and ripping the wrapping off the Christmas presents.

And it doesn't disappoint, believe me. I am so glued to it that I sat with it in Shane's dressing room the other night at the Barbican in London. While all around me fascinating famous people were clamouring for my attention, I tore myself away only to pose for a picture with Ralph Steadman before returning to Christopher Ciccone and his gruesome story.

I cannot begin to imagine what it would be like if one of my siblings wrote a such a book about me. As it happens, my biological father has been threatening to do it for some time now. Indeed, he has assured me that this very newspaper is interested in buying his story. "It will have a sting in the tale," is how he puts it. He promises to reveal to the world just how horrible I really am.

A part of me is shocked, hurt and horrified at the prospect. A part of me is curious. After all, as a child, I did not even know he existed, and only met him for the first time when I was in my 30s, so he missed out on all the really disgusting stuff.

I have absolutely no idea whether Christopher Ciccone has invented stories about Madonna or not. She doesn't appear to have attempted to sue him, nor has she injuncted the book. And given that the libel laws in the UK are highly stringent, and put the onus on the author to prove that a story is true -- rather than on the subject to prove that it isn't -- I am quite frankly amazed that she hasn't.

There are rumours that Madonna has been secretly co-operating with her brother, in the same way that Princess Diana secretly co-operated with Andrew Morton. But I find this hard to believe. Not because Christopher says anything really, really awful about her, but because of the little things that aren't actually crimes, but are nasty. For instance, in one particularly poignant episode (the entire book is packed with these) Madonna invites Chris to live with her in her apartment in New York, and to pursue a career as a dancer. When he quits his job and packs his worldly belongings and does as she says, poor Chris (allegedly) arrives at her apartment only to be told that he can sleep on the floor for a few nights and then he must get his own place. The description of his night spent on a hard floor with only a blanket and a million cockroaches for comfort is worthy of Charles Dickens.

Also worthy of Dickens, or Jane Austen, are the descriptions of his childhood spent fighting for attention from his father and stepmother, after the kids' mother had died of cancer.

"All of us kids are competing for our father's love and attention; but ever the competitor, Madonna usually wins and gets it," he says. "And whenever possible, she snuggles close to our father and pushes the rest of us away."

All kids compete for their parents' attention, and with eight kids and a dead mother, there was probably less than usual to go around. No doubt any child would maintain that his or her siblings got more than their fair share. But the allegations of meanness are more damning.

According to Chris, when their aged and widowed grandmother was hit by a car and was struggling financially and forced to sell the family home, "My sister, who is worth in excess of $600m, opted to send our grandmother just $500 a month."

At some point, he does admit that Madonna lent him $200,000, interest-free, to buy a flat, which he later repaid. But when they toured, (he was her dresser) she had a penthouse suite while he had an ordinary room, which, he says, he deeply resented. It's the little things that make a person look stingy, and stinginess is not an attractive quality.

I wasn't a particular fan of Madonna before I read this book. I like some of the earlier singles, and I like the fact that as a woman who'll be 50 this month, she still wears fishnets and looks sexy, because it means that it is possible for the rest of us, even if we would have to work out for five hours a day to achieve it. But apart from that, I haven't really been interested in her life.

Christopher has changed that. Having read about the really intimate stuff that only a sibling could know, I find that I don't want the book to end, I want him to immediately write another one. Not that I like Christopher, either. If I were to meet him, I would suggest that he should have told her where to get off, when she wouldn't let him fly first class, and when she refused him a suite.

In my mind, he is a doormat, and he should learn to give as good as he gets. But just like in a Jane Austen, this character weakness only adds to the drama, and makes for a more enjoyable story.

Princess Diana always seemed like a sweet, saintly type, but you wouldn't have been able to make a great biography out of her visiting lepers and Aids patients. When the Squidgygate tapes were released, she turned into a flesh-and-blood flawed heroine, and this guaranteed her immortality, in the same way that Marilyn's sordid affairs with the Kennedys and seedy drug addictions did.

Thething about having stuff written (or said) about you is that even if it is lies, people tend to believe it. Marianne Faithfull will go to her grave being linked with Mick Jagger and Mars bars, however much she denies that story. But on the positive side, when flaws are revealed,a person becomes more human, and therefore more compelling to read about. I wonder if Madonna realised this, and was willing to allow her nastier side to be revealed in the hope of becoming more fascinating? We will never know the truth.

I also wonder if the same thing would happen to me -- if one of my siblings wrote about the times that I tried to kill my sister with the bread-knife, and made the little cousins walk the plank, and all the other awful things I did, would that make me more compelling? I sincerely hope so, because at some point those nasty secrets are bound to come out.

- Victoria Mary Clarke