I'm just saying a few positive things about parenting up front, so that no one can say I'm not balanced.

And it's true that many of the delightful aspects of having kids can genuinely take you by surprise - nothing prepares you for how fiercely you will love them.

But the really tough parts of the job don't make it onto the nappy ads and the family sit-coms, and that can throw a lot of us for a loop.

When my kids were little, I remember older parents saying things like, "You think this stage is hard - wait until they're teenagers!"

I would nod and smile - it wasn't as if I could argue - but I secretly believed that couldn't possibly be the case.

They'd simply forgotten what it was like: being beholden day and night to a self-absorbed megalomaniac (or possibly several of them).

I, on the other hand, liked teenagers and looked forward to having a few in the house.

Well, pride goeth before a fall, baby.

Because a teenager is just another kind of self-absorbed megalomaniac. Surprise!

Both little and big kids can push their parents to the limits.

And not just in the way that some say - that the pressures are physical when they're small, emotional when they're teenagers.

Because total exhaustion can feel a lot like existential despair, particularly when you're holding a screaming baby at two in the morning.

Meanwhile, keeping up with teenagers' packed schedules can leave many of us begging for a day off.

And that's just in average circumstances.

To the parents of kids with disabilities, or to those doing it alone, or carrying some other burdens that tip the balance of sanity, you have my profound and humble respect.

The truth is - parenting is hard because relationships are hard.

Especially when you throw in the fact that most of us grown-ups are actually self-absorbed megalomaniacs too.

We've just learned how to hide it better.