My son may join us for 4 nights of our 14 night stay. He won't arrive until the end of the first week. How will this work if we are all in one room and are using the dining plan? Will we have to get the dining plan, buy the 10 day park hopper and pay the extra $ for him in the room (he is 19) for the full 14 nights? Would he then receive the full 14 day credits on the dining plan? He would love to hit every 2 TS place for lunch and dinner. Will we have any problem checking in if he isn't there when we check in?