Caelee did understand, but that didn't mean she wanted him to beat himself up over what happened.
"You can't know that it would have made a difference," she argued softly. "I know how you feel, believe me. I keep thinking if I hadn't moved or if I'd been there with her, I could have been driving instead of her or maybe she wouldn't have even been on the phone, but we can't- Blaming ourselves isn't going to bring her back."
She didn't want to argue with him. That was the last thing she wanted, but she didn't want him blaming himself for this, either. As horrible as what happened was, she knew it was an accident. She knew there really wasn't anyone to blame and the idea that Trace was feeling so guilty over it - she hated that.