Look, I'm telling you now, before you judge me too harshly on what I'm about to reveal, that apart from taking lots of photos I'm not an overly gushing parent. I find lots of baby and toddler stuff that I must do with my two-year-old quite unbelievably dull; about as stimulating as watching repeats of the weather forecast in the dark.

These first two years that everyone said would go so quickly – for much of it, the minutes have passed like hours. Not that the slowness has made my memories any clearer, as I still have no idea where I put, say, the lock of hair from her first haircut that I said I would keep forever, or if her first word really was Abu, followed by Hamza, or was it merely cat? She definitely said both – but when? I'll have to check my Facebook updates. Or the log at GCHQ.

So it is in the context of this lack of precise gushingness that I must make this confession. My daughter has recently become obsessed with the size of her poos – and they are all big, according to her, whether they look to me like they came out of a greedy Jack Russell or a sickly church mouse. "Big poo, Mummy," she says, in awed tones – awed by her own bottom. "Big poo."

This is not my confession – it's all pretty normal, according to Freud and co. My confession is that I, in turn, have become desperately proud of her pride.

I'm so in love with her big poos that I can't bear the idea of them stopping. Of her realising that they aren't things you want to show off about. Of the day when somebody makes it clear to her, whether by accident or design, that sweet little girls aren't supposed to describe the massive steaming achievements cruising out of their bums, propelled by the wonders of peristalsis, into the marvels of the plumbing system. That curly little blondes such as she should desire to be small, and contained, and clean, and dress up as pink princesses. And shut up about their dirty selves; already, enough.

I dread the day those whopper turds have got to go.

Of course, it's no coincidence that her current fixation with size has ballooned while we are on holiday in California. When I decided to bring her here for several weeks and wondered about the possible side-effects, I imagined her learning to pronounce aluminium wrong, or developing a taste for pork burritos, or falling as hopelessly in love with the CNN newsreader Anderson Cooper as I have (the nice man recently came out). I forgot that what this country would really do to is show her size. Everything in America is so much bigger than it is at home.

The fridge in the place we're staying is enormous. The carton of juice inside the fridge is twice the size of the ones at home, and the egg box has not six but 12 eggs inside it – in fact it looks less like a box of eggs and more like a police line-up of anonymous Twitter trolls. I watch my child taking all this in with her wide eyes, and listen to her hamming up the dimensions of her bowel movements like a Hollywood producer. Why, she really has absorbed the local culture here in Los Angeles – she takes those little poos of hers and turns them into stars.

And I think about how much of what girls do is about making themselves smaller. Wanting to suck their waists in and be thin. To not have said so much in public, with such an impact. To be like Hello Kitty – all smile, no mouth. I remember well the years from 12 to 14, where I learned to step back from the tests, step back from my brains, because girls weren't meant to initiate. Girls were meant to follow the boys, and I adored those funny boys. Who so often took our jokes and said them a little bit louder. A little bit more – big.

A friend told me yesterday that her four-year-old announced she had done a poo "like a brown dolphin". Another friend remembers her little sister sitting on a potty and saying, "Look! It is a beautiful golden sun!" before they all waved it goodbye, discussing the beautiful sunset as they flushed it down the loo. I know I must, but I am resistant. I do not want to flush my daughter's beautiful sunsets down the loo.