Here are a few reasons why you might be asking this:
* The famous sheep: You might be thinking of Dolly the sheep, the first mammal cloned from an adult cell. She was a very famous sheep!
* A specific person: Perhaps you know someone named Dolly and are wondering if there are others.
* General curiosity: You might just be wondering how common the name Dolly is.
If you're wondering about the specific person you know, the best way to find out is to ask them!