I leave a message on my son's mobile and, miraculously, considering it is usually "it wasn't charged, mum" and "I've got no credit, mum" and "I didn't hear it, mum" and "clear off, mum, you interfering old busybody and loon" which he doesn't say, but is possibly what he really wants to say - he actually returns the call. "Darling," I say, "you actually returned the call!" "Mum," he says, "what do you want? This is costing me."

"OK, sweetheart," I say, "since you raised the issue of cost, where to start? When you were a baby, and it was Mothercare every four minutes for Moses baskets and cots and changing mats and this car seat and then that car seat and more babygros and nappies and buckets and buckets of Sudacrem for your spotty little botty and the creases in your little fat thighs? I'm not the perfect mother, I admit, but no-one can ever, ever say I stinted on Sudacrem, you got that? Good.

"Now, where were we? Oh, yes, let's not forget the childminder and high chairs and going doo-lally on the credit card in the Early Learning Centre for noisy rattles and squeaking playmats to stimulate your mind so you didn't grow up into a right thicko, like your father, and even that thing you hang in doorways and you so loved to bounce in until you all but bashed your brains out on the door jamb, which was awful, or would have been, but I did get 10 minutes peace while you were out cold, which is always enough time to catch-up on Hello!, so long as you only look at the photographs, which is wise. I don't have much to pass on to you, as there will surely be no money left, but here is a good tip: just don't bother with the words in Hello!. It is always: 'So, Jerry Hall, would you like to tell us what makes you so gifted and divine?' It is never: 'How come you look like you dye your hair at home? Are you too mean to get it done properly?' Now, don't get me started on Davina and Andie saying they dye their hair at home because they are worth it, as I just don't believe them, do you?

Let's skip babyhood

"OK, for brevity's sake - and because I respect you will have to pay for this out of your own money which happens to be the same money your father and I give you every month - let's skip babyhood and go straight to first shoes, then second shoes, third, fourth, fifth ... and summer shoes and winter shoes and football boots for soft ground (studs) and football boots for hard ground (pimples) and cricket spikes and tennis trainers and trendy shoes which have to be replaced by trendier shoes because the initial shoes are no longer trendy because no-one's into Etnies anymore, mum, the skate look is just so over, where have you been?

"And then there is the petrol and the car depreciation involved in ferrying you from this friend to that and whizzing you back and forth for guitar lessons and swimming and whatnot and sometimes just ferrying and whizzing you for the sake of ferrying and whizzing you because it wouldn't do for the neighbours to see the car parked outside the house all evening as they might assume we were neglecting you on the extra-curricular front which, in middle-class circles, is as bad as saying that Sunny Delight is OK and, you know what, I actually quite like it, yum, yum.

"And then there are the birthdays and parties and Christmases and 'can I have a fiver to go the cinema?' and 'can I have a tenner to go bowling?' and I never see the change, do I? Don't interrupt, it's very rude ... what about our days out to Thorpe Park and Chessington where I always have to pay full whack to get in even though I'll only ever go on the tea cups? And those week-long school trips which cost an arm and a leg plus the expense of having to buy you a new toothbrush and bar of soap although I admit that, as both always come back in their original packaging, I could return them to Superdrug for a full refund or, failing that, a straight swap for Canesten for your ringworm as that is where not washing gets you, but do you ever listen?

A mother's love

"And, while we are at it, which we appear to be, let's not skim over the emotional cost: worrying when you are home late; when your temperature shoots up; when you bash your brains out and I don't know whether to call an ambulance or take up Hello!; when the ringworm goes to your nose and I know you'll never get married as only a mother can love someone with ringworm on their nose. And just think, honey, about all the energy I've not put into your food/bowel happenings (What did you have for lunch? Have you been today?) and how much I have put into assessing the weather conditions and deciding what outer garments I must press upon you, like coats and jumpers, none of which will be seen again because you will leave them on the bus and who has to pay to replace those, hmm?

"Which reminds me, the reason I called is that I won't be in when you get home and as you've lost your house keys for the 43rd time and I can't face going down to Bishops to get another set cut because, as it is, the man who cuts them imagines I have the hots for him, as I'm in there every other day, I'll just leave my set with Jane next door... hello? Darling? Hello?..."

d.ross@independent.co.uk