You might consider hunting around online for several weeks to learn values. Check sold prices. Inventories change quickly and Anne Geddes dolls are all over the place. This should be a clue as to value. High volume on sale + low demand + low value. The dolls are not old and were made in the 1990s. Items mass produced for the collector's market does not usually increase in value, due to the sheer amount of available product.
I have seen the plush bear costumes doll (without a box) offered for between $13.00 - $15.00. Since your doll is in pristine condition (I am assuming because it is boxed) and in the original box, it may be worth a bit more.