Listing in 2 age ranges isn't necessary on our site because:
1. Our search allows users to search across multiple age ranges. For example, people can search the age ranges 8-10 AND 10-11. So if your dress was listed in one of those ranges, your listing will show in the search results.
2. When using measurements to search for listings, age ranges aren't used.
Added in Seller FAQ on 23rd Mar 2016