I checked with the service desk and they said they would either give you cash or in store credit. You could even make another purchase as a non-member with the money. Their return policy is generally; if youre not satisfied with it and 50% of it remains, they'll give you a full refund.
They don't carry many diapers but you may want the person with the rec e opt to return them.
They take almost anything back with out question. You could always call their customer serve first.
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