Washington state has something similar. Your example is a specific law for a specific act. In the absence of such a specific law, there are always other laws that could apply.
Basically, prosecutors look at the act as either being “ordinary negligence” like running a stop sign with no other violation and killing someone while doing so or “gross(criminal)negligence” such as running a stop sign at high speed or while intoxicated and killing someone.
If they determine that the act was ordinary negligence there will be no criminal charges. Gross negligence usuall brings criminal charges. One way an ordinary negligent act gets elevated to a gross negligent act is by repeated acts of ordinary negligence such as going out to the car multiple times and moving it without noticing the child in the car.
All I can say is that it appears this was a pattern for this woman.