At 3:28:10 in the clip below Agent Tammy Lee touches on a critical aspect of the evidence. I discuss it in detail in ANNIHILATION. She’s trying to confirm how Bella sustained the gash to her frenulum, an atypical artifact of asphyxia.
Remember, to strangle someone one typically closes off the throat area, and if the mouth is covered, it often includes closing off the mouth and nose. One could expect pressure on the lips but not upward, vertical pressure.
One wouldn’t expect strangulation to include throttling the throat and closing off the mouth and nose, and especially not for a relatively weaker victim like a toddler.
In the clip Watts tries to account for this anomalous injury by explaining how Bella’s head tossed from side to side as he throttled her under a blanket. But that doesn’t work either. To cause that sort of injury there would need to be jerking in a vertical nodding type motion.
In any event, a 33-year-old man would have almost no problem subduing a 4-year-old girl in a vice-like grip around her mouth and neck, assuming that’s what happened. If Watts was able to subdue his wife with no defensive wounds, and almost no wounds to her, then why did he have so much difficulty with Bella?
His version is that because Bella was murdered last, she fought back the most.