From New York Times, I'm Michael Bobarrow. This is the Daily.

Much of our understanding of what makes us who we are revolves around the role of our parents.

Today, my colleague, Susan Domino's, on the unseen but surprisingly powerful ways that our lives are

shaped by our siblings.

Music Our siblings. It's Tuesday, May 13th.

Hi, Sue. Hi, Sue.

Hi, Michael.

It is really nice to see you.

It's so nice to see you, too.

I want to jump in.

And I want to have you tell the story of how it is you became so interested in the subject of siblings.

So I think it started when I was a young child, and my parents used to go away pretty often

and travel for work. And when they did, I would stay with really close family friends.

And you may know that when you stay with a family, you really get to know them

and their culture in a way that's different from your own family. You can really see all these

big differences. In one family I stayed with, the kids would do these very elaborate math

problems, like at the table, you know. At the dinner table? At the dinner table. One, the father

would say, so Daniel, a plane is leaving Chicago

traveling this many miles an hour,

and another one is leaving New York.

What time would they cross paths in wherever, you know?

Oh my God, what are you thinking when that question comes across the table?

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