What is it about boys and their toys? asks Jo Malone

We're renovating the bathroom at home. Well, I'm nodding as Rob talks about radiator sizes and water pressure and I hold the door open while he carries things in and out.

But, as the more than capable practical one in the house, he's doing the work.

It had to be done, it had reached the point where weekend guests would eye up the dilapidated shower which no amount of scrubbing or bleach could make look anywhere near decent and say, as politely as they could, that they were going to the gym when they got home and would have a shower after that.

Superstar Rob can definitely picture it finished, whereas I do struggle to see past the dust that's already getting everywhere, the temporary shower in the corner, the piles of towels and toiletries that have taken over every other room as I don't know where to put them (and why do we have 14 open bottles of anti-frizz hair conditioner?)

I'm muttering about cupboard space and how we need at least as much as we had before when he starts talking about the outside drainage again. He's mentioned it a lot, something to do with pipes and trenches.

'I think I'll buy a digger,' he says. 'It'll come in handy for other things too.'

He's explaining how a secondhand one wouldn't be that expensive and he wouldn't have to worry about trying to cram everything into a day if he hired it, and so on.

I really don't want him to have a digger.

He may be a gorgeous husband, and a top dad, and very talented, hands-on, technically minded and so on. But he's a boy, and a digger is a boy's toy.

I know that within a week of owning a digger he'll have dug trenches and then he'll turn round and eye up all those other areas where 'a mini digger would be really useful.'

The drive would get 'landscaped,' various trees, bulbs and bushes would disappear, he'd dig the footings for the shed he's been promising himself for about eight years, and then, before I had the chance to grab the keys, the garden would gain the koi carp pond he's always wanted and the rest would be turned into a trials' bike course with jumps, banks, hills and dips and some kind of splash zone.

I'm telling my running friend Sarah my concerns, and she announces that her husband has a mini digger. I sigh.

'He loves it, he's always finding excuses to use it,' she adds.

That's my worry, that Rob won't just love a new toy, he'll get obsessed with it.

But what if Rob mentions his great digger-owning desire to my far-too-helpful brother, who has a plant hire business?

He's bound to have a plan involving a machine appearing at our house. I need to come up with a better plan, quickly.