Making a 3-year-old see logic

The girls and I were at my aunt's house this evening, and we got home slightly past bedtime. We promptly started getting ready for bed. Claire pulled off all her clothes and had some difficulty taking off her shirt. Then I started getting Natalie's jammies on to give Claire practice at putting on her nightgown herself. This is a task I have observed her perform several times.

Claire (ready to have a 3-year-old meltdown): I can't do it!
Me: Yes, you can. You've done it before.
Claire (melting down): Noooo I caaaan't.
Me: Well, when it worked before, what did you do?
Claire (pulling nightgown over her head): I did this.
Me: That's right. Then what?
Claire (putting arms in sleeves): This.
Me: Claire, you know what? You just put your nightie on.
And she looked at me in utter perplexity.

I could not believe the trick worked. It felt like one of those ideas you read about in parenting books and parenting magazines and parenting websites that no matter how you try, they never seem to work. But it worked!