For an Ornament party, do you bring a wrapped ornament?

I have a lot of Christmas ornaments that my mother gave to me. My sister in law is throwing an ornament party. Would it be ok if I brought the ornaments that Mom gave me instead of going out to buy one? They are in great condition - like brand new. There are so many different kinds. I only hang a few on our tree. I have browsed ornaments at stores but didn't find anything so different from the ones I have. Knowing my sister in law, I don't think she would care at all. She's a sweet person - funny too.