My Fabulous Life: A right royal fancy-dress knees-up...

Yes, thank you, I did have the most super time at Prince William's 21st birthday party last weekend. I do not know the Prince that intimately, I admit, but I became very close to his mother, the late Princess Diana, through our tireless work for Aids victims, even though I stopped short at touching them, because I didn't want to catch what they had. "Don't touch, don't touch, not a hug, for Chrissakes... Oh yuk, ma'am, you've really blown it now," I would shout out to her as best I could from where I had positioned myself just outside the ward, with whatever pastel-coloured cashmere jumper I happened to be wearing that day pulled well up over my nose. Now, of course I am not saying that the princess's eventual, tragic death was in any way Aids-related. But all that touching probably didn't help.

Anyway, a fancy-dress party on an Out of Africa theme! What fun! The key to fancy dress, as in most things, is planning, and our preparations began a fortnight before the event, when I forbade Keith from eating, and had Mae train some flies to crawl over his face. Then, on the actual day, after drinking 675 litres of Evian - which, I assured him, would have the added benefit of being wonderfully hydrating and detoxifying - he looked very much the part: swollen-bellied, with hollow, hungry eyes and those flies going bzzz, bzzz. I'm afraid to say, vain though it sounds, I really did clap my hands at my own cleverness, and do believe Keith would have joined me "if only I didn't feel so faint, Den".

As for myself, I thought about going as the Aids virus, which almost certainly came "out of Africa", but I could not think what shoes it might wear, so in the end opted for an off-the-shoulder peach satin dress, turban and jolly false beard. "You look more Middle Eastern than African," said Keith, once I had brought him round with Jo Malone's Lime and Grapefruit Incredibly Reviving Smelling Salts.

I said: "Stop flapping at those flies! And go and get blacked up, darling, or we'll be late."

Actually, we were among the first of the 300 guests to arrive, along with Ex-King Constantine of Greece, which was an extraordinary stroke of good fortune, as I am planning Keithleen's next birthday party (I've told her she wants a Harry Potter and the Order of the Phoenix theme) but am having trouble ordering the phoenix. "Your Exness," I said to him, "I've tried Harrods, but all they will say, rather unhelpfully, is that the phoenix is Mythical. Tell me, is Mythica near Ithaca - where I once hosted a very pleasant yoga retreat week - and, if so, do you know anyone there who might send me one?"

Alas, I did not catch his answer, as we were approaching security by then, and I thought it best to confess to Keith at that point that we did not have invitations as such. Keith sighed and said he suspected as much. I was going to say, "There are no flies on you," but then realised that there were. Instead, I said that, invitation or no invitation, the late Princess Diana would have wanted me to be there because, aside from our tireless work for Aids victims, we also did a lot together for the Great Ormond Street Children's Hospital, which was heartbreaking, but not as heartbreaking, as a lot of the children, lying in bed covered in wires, were obviously undergoing their first Slendertone treatments, and I do believe it's never too young to start. Indeed, Keithleen, who was hooked up almost immediately after birth, is now three and showing no signs of cellulite.

So, no invitations as such, at which point Keith said: "This is the last straw. I'm off." And I do believe he would have been off, had he not fainted again, which was lucky, as I could then use his stomach as a mini-trampoline to jump over the castle wall. I was worried about Keith, of course, especially as all I could now hear from the other side was a watery gushing sound, followed by bzzz, bzzz and then a weak: "Help." Naturally, I would have done my best to assist him but, thinking of Princess Diana, knew I had to press on to the party, which I did, and... wow! Live monkeys, model elephants, and Earl Spencer dressed, somewhat lazily, I thought, in a safari suit. Still, I stopped to commiserate with him about his sister. "All that touching could not have helped," I said, with my head cocked at a compassionate angle. Emma Thompson was there, too, but she has lately given up the theatre for, yes, working with Aids victims in Africa. Obviously, I did not shake her hand, but I did wave to her from a distance in what I hope was a friendly manner, while pulling my peach satin dress well up over my nose.

Anyway, when the birthday boy got up to thank his guests for coming, I too thought it was time to say a few public thank yous, so I took the microphone and said: "Ladies and gentlemen, thank you so much for all your support over the years. Indeed, next week sees second print-runs for not only Shopping for Ribbons but also How to Maintain Your Bird Bath... "

.. but Her Majestyÿs hospitality was lacking

I am now back home. A super party, as I've said, and the Queen even put me up for the night in these apartments that, I now know, she keeps in the West End. Actually, the accommodation was shockingly poor, with no en-suite, bars rather than lined drapes at the windows, and rather gruff staff who, having not got the Out of Africa theme, were dressed as policemen and kept quizzing me about the urine-soaked, fly-covered tramp that had been found lying at the base of the castle wall. I said I did not know this person but, being a tireless charity worker, I would, if they sent him my way, consider taking him in... See you next week!

Denisella@independent.co.uk