I think that the OP is referring to the 1 or 2 person rate of occupancy in a double room, not whether 2 persons can share a single room(which is a definite no-no unless you are v friendly with your travelling companion!). The hilton terms are very clear, it is SPOUSE stays free. I always book the 1 person rate when I'm with WelshBoy , but if travelling with anyone else I want 2 beds ( as I expect the OP would if travelling with Mama) and I pay the 2 person rate. If you want spouse stays free I guess you would be given a King not a twin room. Not worth the risk.