Julie, you know, I've got two loving kids.

You've got kids, too, right?

Yes, I've got two.

I'm not sure how loving they always are,

but I've got two also.

You know this is being recorded, right?

Oh, yeah, that's fine.

I wouldn't tell you about a study that I did a while ago.

This was probably one of my first ideas.

I was in grad school, I was living in Chicago,

and I was interested in this question

of the impact of children on marriages.

And at that time, I thought,

is there a way to find a natural experiment

whereby some couples by chance are exposed to more kids

and other couples are not?

It turns out there was a way.

The challenge with that kind of study

is that you can't simply compare couples with more kids

to couples with fewer kids

because those couples are different for all kinds of reasons.

What I needed was a situation

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