Sweet story about twins.

I wanted to write a story about twins, girl and boy who were very close, perhaps right up through High School and longer perhaps. As twins sometimes do, they played games with their parents, switching clothes and so on.

I read this story more than 10 years ago, I think. Since the Author was so much better than I, It seems that it would be better to read their story rather than my own.

Has anyone an idea where I might find this story?

Thank you

Gwen