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Identical Twins are identical, right?

Well, not completely, and especially not when it comes to autism spectrum disorder.

Here to chat about this is NPR's resident brain-of-file John Hamilton.

Hey John!

Hey Gina!

Okay, so I understand you've been reporting on autistic twins as part of the NPR series on the science of siblings.

I have and I was lucky enough to spend some time with a pair of identical twin brothers who are at

really different places on the autism spectrum.

Their names are Sam and John Fetters.

They are 19.

They are very tall.

Sam is 6-5, John is six four.

Here's how Sam describes John,

who is sitting right beside him on the couch

while we talk.

He's so smart.

He knows like, you know like every single episode of Sesame Street and the Muppet show.

Yes. He has them all like stored in here in a way that is frankly extremely impressive to me.

And here is what John says when I ask him to describe his brother.

He's Sam.

He is definitely Sam and what does Sam like to do?

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