There's a Man in My Wall

The following is an email from a friend who answered the question.  I was going to re-write the post in my own language, but thought it was just too colorful to change it.
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So...something kind of creepy I guess.  My daughter, who's six, told me there was a man living in her wall.  That's not the creepy part, she says shit like this all the time.  A few weeks ago she told me there was a castle behind the old stationary factory down the street (there's not by the way, it's a sub-development).  Anyway I started grilling her about the man in her wall.  This was her mom's idea.  She thinks that, though her imagination is great, it's getting out of control and bordering on lying.  I think it's usually cute, but that's a fight I lost.  Anyway I asked her what the man's name was, how he got into her wall and like fifty other things.  Mostly she said she didn't know (you can tell her mom's a lawyer huh?). 

So skip forward to three days ago.  My son, who's fifteen, is in geometry class.  His homework assignment was to figure out the square footage of our house.  I was helping him (you'll notice my mathematical confidence is high when I already know the square footage of the house).  He was told to measure all the rooms from the inside and then measure the house from the outside to give him a rough estimate I guess.  So there was a difference.  I figured it had to be because the walls took up some space.  But the difference between his measurements of the inside of each room was like twenty to thirty feet different than what it was supposed to be (i.e. what the real estate agent had told me it was).

At first I thought that the boy and I had something in common, we suck a math.  But I checked his measurements anyway, room by room.  Ready to be creeped out?  My daughter's room was the cause of the problem.  I still have a copy of the deed (I mentioned my wife is a lawyer right?) and it had a little blueprint of the house in it.  I checked the dimensions for my daughter's room 10 feet by 25 feet.  My son's measurements were 10 feet by 22 and a half feet.  So there's this extra twenty-five feet that's on the paper but not in the house and that seems not to jive with the measurements from the outside.

Check your math, I think, and measure the room from the outside.  I measured the hall that goes along the one wall and my master bedroom which shares the 10 foot wall.  Guess how long the hall was.  25 feet.  Still missing 2 and a half feet.  The shared wall is on the opposite side from the wall I'm pretty sure is 2 and a half feet too close, which is an outside wall.  I hadn't even thought about the man that my daughter said was living in her wall until this point.  What's a father to do?  I got a knife and a hammer.

My wife was not pleased with this development but by then I think she was pretty freaked out too (especially after I ill advisedly told her about the man living in the wall comment), so she told me just to make a small hole and patch it up right away (I'm Irish, of course I know how to patch drywall).  So, I make the hole in the wall, on the other side was another sheet of drywall.  Keep in mind this is supposed to be an outside wall. I'm freaking out at this point, ready to tear the whole wall down, but I restrained myself. I opened up the first hole and made a hole in the second drywall sheet big enough to stick my head in.  

I got one of those head lamps campers use so I could see and looked around.  It looked like a really narrow hallway.  Ten feet long about two feet wide hardwood floors (like the rest of the house) no doors, no windows, just cobwebs and dust bunnies.  The walls were drywall and looked like they were either perfectly mudded (which they probably weren't judging by the rest of the house) or painted white.  The ceiling too was covered and crisp white.  I was getting ready to make a man sized hole in the wall when my wife put the kibosh on the plan.  She made me patch up the drywall once I told her it didn't look like anyone was in there.

So, what do you think?  I've been trying to find a way into that little room from the outside or the crawl space or something but I can't find anything.  Why would someone do that?  The house was built in the seventies and we aren't the first or even the second owners but I can't figure out why anyone would cut out twenty five feet of floor space.  Also, man in the wall...young girl's active imagination or call the priest?