That won't keep me warm in the middle of the night

In around 300BC, Euclid invented geometry, forever transforming the way people would think about space, measurement and logic.

That don't impressa me much.

In 1859 Charles Darwin shattered his own religious convictions, effectively ruining his marriage and jeopardising his standing in Victorian society, by publishing a book which finally shed light on what remains the most astounding idea in science: evolution.

That don't impressa me much.

On July 21st 1969, Neil Armstrong became the first human to set foot on the surface of the moon. This historic moment was the culmination of the considerable intelligence, ambition and bravery of various NASA heroes.

That don't impr- OK. Enough of the contrived Shania Twain referencing. It seemed like an innovative literary device in my head. I always hated that song anyway. 'Shiny Train,' I used to call her. Because I'm funny. My point is that, of all the great achievements that mankind can boast, none comes close to matching the accomplishment our eldest daughter made last week.

After at least a year of ignoring it, screaming at it, sitting pointlessly on it for fruitless hours at a time, and being caused by it to not poo for days on end, she has finally mastered the full and productive use of her potty. I had to interrupt typing the last sentence to dispose of a brown monster that she laid - without the merest hint of fuss or hesitation - within its confines. She didn't even blink. This was a matter-of-fact faecal production. As I type this sentence she is busy training her doll to use its own toilet in the doll's house. The apprentice has already become the master. She has even taught her little sister to run around the house shouting "POOPOO" in exactly the right joyous tone.

The relief shared by my wife and I at this development is palpable. We have endured many long months of well-meaning friends and relatives enquiring pointedly about her progress. The pointedness was probably a figment of our paranoid imaginations, to be fair. But it's a fact that - while we find it easy to proudly imagine her as advanced in most things - our daughter has been a bit late to the table in this, toilet-based respect.

We have on numerous occasions attempted to be ruthless in withdrawing the nappy option from our daughter. But, invariably, she would simply hold it in until (and I hope that, in years to come, she will forgive me for sharing this) her number one bit got smelly and her number two bit got incredibly painful. Ruthlessness is hard to maintain when your tough love extends to endangering the health of your toughly loved one. So our determination would always expire after a few days or so. Eventually we resolved to be less resolute, deciding instead to take a laissez-faire approach, whereby she would somehow make it known to us when she was ready.

But then we received confirmation that our daughter was to start nursery school in a few weeks' time. Mildly panicked at the prospect of the awkward nappy conversation taking place on her first day there, we had no choice but to go zero tolerance. Perhaps our commitment to the cause was subconsciously strengthened by this new time limit, or perhaps it happily coincided with her finally overcoming her emotional attachment to the nappies, but within a day of our fixing the nursery date we were hearing the blissful tinkle of pee on plastic.

And she has taken to it like a toilet duck to toilet water. At regular intervals throughout the day, she'll announce her impending success as she strides purposefully towards the potty, before pulling down the necessary garments and sitting in the right place at the right time. She has even mastered helping herself to a modest but sufficient amount of toilet roll and having a little wipe. It's like clockwork. Urinatory clockwork.

There has, I believe, been only one notable accident thus far. But the sofa cushions are clean again now, so it's water under the bridge, so to speak.