Last straws may break camels' backs but it was a toenail that caused The Mother to explode with anger.

"Is this yours?" she asked, marching into the kitchen where I was cleaning a battle-scarred, no longer non-stick saucepan.

In her hand, or rather held between fastidious fingertips, was what looked indeed to be a toenail clipping.

"It could be," I said. "But then again, it could belong to anyone. Where did you find it?"

"In the bath," she said. "I sat on it, that's how I found it."

"Then it must be mine, unless it belongs to you," I replied.

"I do not cut my toenails in the bath," said The Mother, somewhat superciliously I thought.

"Where do you cut them then?" I asked, beginning to feel slightly curious, but she had marched off again.

Since she moved in with me, The Mother and I have become used to sharing our living space.

Normally we co-habit in a reasonably civilised, occasionally contented, fashion. When one dusts, the other Hoovers; when one cooks dinner the other mows the lawn.

Our bedrooms are both out of bounds to the other but we share the living room, the kitchen - and the bathroom.

Now if there was going to be friction in any one area I would have nominated the bathroom. The Mother and I both like our toiletries, you see, but where she prefers the whiff of roses or jasmine I adore the clean, fresh smell of lemons and other citrus fruits.

So we keep our smellies well apart. The Mother spreads out on a bottom shelf, while the upper one is my domain. Sometimes the twain do meet, however, and it is not a happy occasion.

"Where's my shampoo/bath oil/deodorant?" The Mother will wail. Or, more angrily, she will demand to know what a canister of athlete's foot powder or a tube of hair removal cream is doing on her shelf.

I get cross when I discover someone has used my expensive soap or hair conditioner and not put the top back on.

"Who? Me?" says The Mother with such a look of wounded innocence that I start to wonder if a third person I've yet to meet has actually moved in with us.

Then there's the cleaning of the bathroom. Baths and sinks are all well and good -- plenty of volunteers in that area -- but who is responsible for the lavatory?

You can only avoid a contentious issue for so long, then the sparks start to fly.

"Well, I've just finished cleaning the lavatory -- again," I say, marching through the living room still wearing my heavy duty rubber gloves and reeking of bleach and disinfectant.

"What's that?" says The Mother pretending not to hear. "You've been cleaning the what?"

"Oh, forget it," I mutter, adding, under my breath: "If I forgot it you'd have the Public Health Inspector round."

There's also the issue of hair down the plughole. "Have you washed your hair in the bath again?" says The Mother in a tone of voice surely reserved for:

"Have you been cutting up bodies in the bath again?"

"Baths are for washing everything -- every little nook and cranny - in," I say.

Yet they are evidently not the places where you cut your toenails, at least according to The Mother's Book of Domestic Etiquette and Harmony.

And she still hasn't told me where she cuts HER toenails.