Eldest rug rat has begun taking interest in my work and was looking at pictures accompanying article I had written about Eddie Izzard.

In one was a short-back-and-sided, dark-haired, goateed, good-looking, leather-jacketed bloke and in the other a glamorous peroxide, purple nail-varnished, high-heeled bird.

"Which one were you writing about?" she inquired, innocently.

To which I replied that they were one and the same person.

"She's very beautiful," she said, much in awe of the sheen of the purple nail varnish and the matching Elizabethan-style dress.

"Actually, he's a he," I told her, going on to explain the basic tenets of transvestism which she seemed to think the most fabulous idea.

(She's been having trouble recently, trying to persuade the five and six-year-old boys she brings home from school to muster much enthusiasm for dressing-up games.)

"Do you want to be a princess, a fairy or a mermaid?" I overheard her asking one particularly tough six-year-old, who insisted that he only wanted to be a pirate.

In the end, this particular boy agreed to put on an Arab dress (which I explained was a man's djellaba, bought from a market in Marrakech by sister who recognised that, although male garb, it would certainly look like a princess outfit when viewed through pre-school eyes) as long as I agreed to let him have a kitchen knife to go with it, so that he could be Osama bin Laden.

He then proceeded to hide in various "caves" (cupboards, under the stairs, under the table, behind the curtains etc.) while a British Marine Commando Unit, comprising just one person (cunningly disguised as a fairy) had to try to find him. This kept the guest happy - but wasn't exactly what the fairy had in mind (that was something along the lines of them both flying around looking for teeth).

So the fairy was particularly interested to hear of the existence of boys who actually liked dressing up as girls and wondered if any of the boys in her class might also be transvestites. I said that they probably weren't quite old enough yet to have decided that they were. She asked me how old Eddie was when he decided he was a transvestite. I checked my background notes and discovered he claimed to have known from the age of four.

She then set off for school the next morning with a mission to accomplish - which did not involve smoking out al-Quaeda suspects from behind the bike sheds, much to the disappointment of Osama, otherwise known as Tom - but to discover which of the boys in her class were transvestites and bring them home for a spot of dressing up and a makeover.

Knowing she is quite determined to see it through when she has a mission in mind, I went to pick her up, expecting her to have found at least one boy who was willing to wear lipstick in exchange for mega-tea. But was instead asked to stay behind for a word with class teacher.

The teacher seemed concerned and told me that while studying other cultures they had passed round some photographs of different national costumes (many of which involved men wearing skirts or dresses, eg Scottish men, Greek soldiers, Arabs, Korean warriors) and eldest had pointed out that they were transvestites.

I was about to explain the origin of her fascination but was pre-empted by the teacher who said in a kindly manner: "I realise it may be difficult for you but it's best if we know in advance if there's anything like this going on at home, so we know how to deal with it when it comes up ..."