My son use to sleep like a rockkkk when he was a newborn! a balloon literally popped right next to him when he was sleeping and he didn't even get startled and didn't wake up.
right now I slowly opened my soda and let the gas come out and he starts shaking all crazy like he just fell ahaha what the hell? now he's such a light sleeper it SUCKS! especially because everyone is so damm loud in this house! -_-