Yes, do doublecheck the suitcase and all its zippered compartments, but also - while it was inside the suitcase, would you have tucked the box inside a shoe or spare purse or cosmetic bag? - look in every item that you had with you on the trip in case you slipped it inside for safekeeping. And, where did you unpack the suitcase - on the bed or a chair or on the floor? - look all around that area in case the box tumbled out while you were unpacking - and if it could have dropped to the floor, look anywhere you might have sort of nudged it with your foot. And, after the trip, did you stick a bunch of clothes into a laundry basket or a drycleaning bundle? Check that out too. I almost always find that something I've lost is close to or linked to the very last spot I recall seeing/putting it... Hope you find it soon!
