The Waiting Families

I know that a few (maybe 3?) families are told to "wait by the door" because they were selected as one of the final families the team may visit....now I was also wondering if they are also told to pack (for the vacation) or if they just do that afterwards...that would suck if you're already on the edge of your chair waiting to see if the team pulls up, but if you also had to pre-pack for a trip that doesn't happen.

I hate the "surprise" factor...meaning they pull up with the huge bus, then it's the bullhorn yell..and that's what they hear? They don't notice the huge bus?