A letter to ...

My daughter's immune system

I'm afraid that most of this letter will be rather critical, so let me at least attempt some even-handedness and start by thanking you for the fantastic job you did on my daughter's behalf for 20 years. I have to say - somewhat grudgingly, in the light of the way that things have turned out - that you were fantastic.

You worked silently and tirelessly behind the scenes protecting her from just about every bug that did the rounds. While other girls were off sick you served and protected mine peerlessly, as evidenced by year after year of perfect attendance at school. Thanks for that, it made all our lives so much easier - for those 20 years.

But you also did your bit in making us all rather smug. We didn't "do" illness; it wasn't an option. We had no language to deal with it. We didn't acknowledge its existence. So when it did come - in spades - we were unprepared.

Now I'm not a medic or a scientist, so I may have this wrong - if so I apologise for blackening your name. As it was explained to me by someone whose own immune system turned on her (do you pass on tips to each other?) it goes something like this: you were so good at your job, so relentless in hunting down and zapping all the nasties that showed up on her radar, that you got a bit bored. There wasn't enough for you to do. So, like a hyperactive guard dog driven to distraction by the tedium of its own effectiveness and the lack of a challenge, you turned on your mistress and savaged her.

Quite why you should target her bowel, I'm not sure. If you had have picked on a toenail then perhaps the consequences would not have been so devastating. Because, yes, my friend, I need to confront you with the consequences of your endeavours, and devastating is not too strong a word.

The debilitating nature of the condition you have caused has wiped out the optimism, expectations and spirit of our daughter. In the space of about two months you have undone your previous good work. And ours. All the emotional investment and all the - irony of ironies - good diet and hygienic domestic regimes laid down in those 20 years. It's no fun when you are 20 and lying in a hospital bed waiting for drugs to kick-in, pondering life with a colostomy. There are better ways to lose weight than by visiting the toilet 12 times an hour.

I'm sorry if I'm getting bitter. It's partly that I can't do much to help her. I know you were only doing your job but you did it pretty badly - or simply too well. (I can't really make up my mind on this.) Either way, we've all got to live with the consequences of your actions.

If only you'd been just a bit more ... mediocre. You know, zap the important bugs, but let a few through; take life a bit easier. But, no, you had to be a bloody zealot, didn't you?

Yes, my friend, if there were more like you - workaholics - then for sure British industry wouldn't be in the state it's in, eh? If I am wrong then I humbly apologise. It's just kind of good to have a scapegoat for all this - and as Mrs Thatcher would attest, there are few better to cast in this role than the "enemy within". I just hope you are proud of yourself.