I am a single mother of five-month-old twins, and believe me, I know how that sounds.

Even without the single mother thing, my life at this point should be chaos. I should be frazzled, burnt out, panicked. I went back to work a few weeks ago (I live in New York, where standard maternity leave is 12 weeks, and anything over that is considered wildly decadent and European) and I should be experiencing the catastrophic schism between my old and new identities. I should, in short, be a total wreck.

And, of course, I'm exhausted. On those days that I don't have help, I constantly run circuits of my apartment, ferrying dirty muslins from the sofa to the laundry, dirty bottles from the bedroom to the kitchen, and dirty babies from the high chair to the changing table, to the bouncy seat to the buggy.

I'm pretty sure the mileage is equal to a marathon a day. At night, things are either blissfully calm or resemble a hellscape by Edvard Munch.

I was prepared for these things to happen. They are simply the cost of having kids and I judged my two girls to be worth it. What I didn't expect is the ways in which the babies have made my life easier.

In the broadest of terms, the two things that keep people awake at night are versions of the questions, where am I going and where have I been?

Or rather, what am I doing and what have I done? Before I had the babies, the background condition of my life was one of contentment combined with vague anxiety. Was I where I wanted to be? Had the conversations I'd had that day gone the way I wanted them to? Were the decisions I made five, 10 or 15 years ago the right ones? What was I doing tomorrow?

All of that fussiness has evaporated in the furnace of my babies' first five months. Firstly, nothing keeps me awake at night. Nothing. I lie down and am out cold in two seconds.

Second, once you have a kid, regrets about your past become inadmissible. As in Back To The Future, every single detail of your life prior to conception had to have happened precisely as it did in order for your baby or babies to have been born. There's nothing mystical about this; it's a function of evolutionary psychology- the way we look at our babies and judge them inevitable - but no less powerful for that.

Other things become easier, too. You get twice as much done in half the time, simply because you have to. Motherhood is supposed to involve a huge amount of guilt, but I have found it to be the opposite. (Single

parenthood in this scenario is easier than its alternatives; I have to work or none of us eat, so I never feel guilty about having a nanny.) Before I had kids, I would spend weekends longing to pass out and binge-watch TV, while feeling obliged to go out and improve myself.

All that has gone. The tiny bit of downtime I have between feed cycles is spent lying down and I don't feel the slightest bit guilty; goddamnit I've earned it.

The biggest shift, however, has to do with this cliché about kids giving one's life 'meaning'. I've always thought it nonsense; my life was perfectly meaningful before I had my girls, and it would have gone on being meaningful had I not had them.

What having a baby does do, is get rid of the anxiety around 'meaning' in the first place. We are constantly being told to live in the moment and nothing enables this like wrangling two babies. There is something quite lazy about having children. You don't have to justify yourself to the same extent any more. 'Oh, look, you think, I did something important!' Or rather, 'I did something quite important.' Or, at any rate, 'I did something.'

Having a kid shouldn't qualify as an achievement - it's a form of self-gratification like any other but society considers it one and frankly, I'll take it.

And of course, having babies makes you value things you took for granted before. Free time has never been more precious. I have never enjoyed simply sitting down as much as I do now. Every day I get the girls in bed by 8pm is a huge achievement. I was in my late 30s when I had them and pretty jaded. Now I watch my baby laughing hysterically like she just smoked a joint and is wigging out at the shape of a leaf or a Coke can, and everything is fresh and hilarious.

All of these things are incredibly ordinary. But isn't valuing the ordinary a definition of happiness? I look at my babies and think, 'Yes, of course, you two. How lucky I am.'

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