Hedgehog Escape!?

Ok first thing to be aware of... the hedgehog is only going to be moving around at night. If your brothers close their doors at night then she is more than likely not in there. What is the temperature in your house? If it's below 70F then you really need to find her b/c she's probably attempting to hibernate and will not be moving anymore at night. If it's above 70F then setting a trap may work, but it's still a good idea to keep looking.

Hedgehogs, in my experience, are not amazing climbers. They can climb up small ledges, but they aren't going to climb into your bed or anything like that. Check all the areas on and close to the floor. If you have furniture with opening in the bottom (recliner chairs for example) flip them over and check them. In the bathroom and kitchen check to ensure the cabinets on the bottom are sealed completely so there's no way she could be under the cabinets. It's hard to explain this, but stick your hand along the bottom and ensure there's no way she could have climbed up under the bottom panel of the cabinet (I've had one hide there). She is looking for a snug, dark place, and if it's warm that's even better. She may be under a pile of clothes or in a shoe, etc. Just keep looking and you will eventually find her.