Originally Posted by Anna Phor

If it were me, I'd do the airport Marriott. Close by, has a pool.

Arrive at Dulles, check in to your hotel, eat dinner. Swim for as long as it takes to tire the kids out. Leave as late as you can, and try to transfer sleeping kids into stroller/carrier. Hope and pray that they stay dozy enough to sleep an extra two hours once you are on the plane.