Is it a secret?

I'd never given much thought to the two words, secret and surprise, but my three-year-old (amusingly, she insists that she is four, and that she's already had her fourth birthday party) daughter insists on distinguishing.

It's kind of funny, because she repeats that a surprise is never told, but a secret is.  She's got it backwards, but she has figured out the essential difference between the two.  Kind of cool when that happens.