Don't you just love it when your LO has been sleeping about 40 minutes and has started to squirm just a little (which you know because you're watching on the monitor and they squirm at 40 minutes like clockwork every single nap), but it's pretty clear they are going to go back to sleep for another sleep cycle this time (yippee!), and just when you think they're asleep again, the dang house makes a big POP noise, and you see them jump in their crib?!?!? You think "Noooo, please let him go back to sleep!"
Or is this just something we deal with at our house and no one else has noisy walls?