My toddler loves this mouse backpack, and I do too! It holds a surprising amount for its size... Which is just small enough for my 18 month old, and will fit perfectly for several years to come. We use it for a diaper bag... It holds a changing pad, several diapers, a snack, and her sippy cup just fine, with room for more if need be. The side pocket holds her drink fairly securely, but could be a tad deeper. The front zipper pocket is roomy. It arrived a day ahead of schedule. We are both really happy with it.