What it actually says is they believe they were asleep before they were attacked. That leaves room for the possibility that any of them could have been asleep but awakened if they heard noise, if they had to use the restroom, etc. We also know that they didn't all end up in their beds. At least Ethan ended up on the floor, reportedly in the hallway outside his bedroom. In my opinion, X also awakened and fought the attacker and sustaining defensive injuries. If so, she could have ended up on the floor against the wall of the bedroom, which could account for the blood stains on the exterior of the house where located. (Although various media outlets reported that was blood, we can't be sure those reports were accurate.) In this photo, the corner of the house facing the camera front and slightly left is where the "blood" is located. Just on the backside of where the 2nd level meets the 1st level right above the sloping ground. If X ended up right against the wall there, it's possible enough blood could drip out if there were cracks where wall met floor there. We know that the floors are not carpeted, and the laminated surface may shed liquid that direction rather than absorb it. This is all speculation, but it seems a possible scenario.
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