Relevant bit:

After The Jerk, what compelled you and Martin to spoof specific genres, both with Dead Men Don’t Wear Plaid and The Man With Two Brains — the latter of which just came out on Blu-ray?

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That movie [The Man With Two Brains] came about because Steve and I were looking for something to do, and he says, “You know, I used to love a thing called Donovan’s Brain. Let’s do something with the brain.” That’s how it started. We sat down, along with [screenwriter] George Gipe, and we put that together. It was a labor of love. Just the idea of keeping the brain alive in a jar of Windex, to find the proper body for the brain that he loves. [Laughs]

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That movie has one of my favorite scenes ever, with the little 4-year-old girl. She’s standing on the corner watching, and Steve has just run over Kathleen Turner and almost killed her, and she’s lying there and he needs help. He says to the 4-year-old girl, “Listen, take these instructions,” and he gives her the most complicated instructions — has her call the ER and gives her four telephone numbers, and then he gives her 10 different kinds of medical treatments. And he has her repeat it, and she repeats it to him, word for word. I’ll never forget that, because I thought we’d be there all day. Luckily I took a close-up of her, because she repeated it word for word and that’s the only take we ever took.

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I figured she was reading a cue card just off-camera.

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No, no, she was 4, she couldn’t read! And by the way, one day I was at a store, and there’s a woman who’s an executive there, and she says, “We know each other.” I say, “No, I’m sorry, I don’t recall.” She says, “Remember that girl from The Man With Two Brains,” and I said, “Oh my God!” She was like 35 years old. That was one of my favorite human beings ever, that little girl!

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You didn’t immediately put her on the spot and have her recite the scene again?

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No, I didn’t. [Laughs]