My wife & I and 3 kids (8, 8, & 11 y/o) are considering taking overnight trains from Cordoba to Barcelona, and then from Barcelona to Bilbao. We're hoping to reserve a 4 person room and let the little guys share a bed. We think the kids will get a big kick out of sleeping on the train, we can travel at night, and we can save on hotel costs.

Any thoughts on logistics and safety will be greatly appreciated!