Not the concussion?
"I'm sorry, I don't understand," Ethan's father said, his voice trembling. "If the fall isn't what's keeping her unconscious, then what is?"
Dr. Evans sighed, a look of professional frustration on her face. "That's the million-dollar question. Her brain activity is... unusual. We've run every test we can. There's no sign of further injury. In fact, her brain is showing patterns remarkably similar to someone in the deepest, most restorative phase of sleep. It's almost as if her body, in response to the trauma, has put itself into a forced, ultra-deep healing state."
She looked at their bewildered faces and tried to simplify. "Imagine your body has a 'factory reset' button for when it's completely overwhelmed. It seems your mother's brain has pressed it. It's a rare neurological response, but not unheard of. It's healing itself from the shock, and the best thing we can do... is let it."
"So she just... sleeps?" Sarah asked, her voice filled with disbelief.