The question is...
If it is an arrestable offence (which it should be) to leave your child unattended in a car in a shaded parking lot for 40 minutes then why isn't an arrestable offence to drag your child across 20 to 50 miles of desert in the searing heat with no water and no place to take shelter?
In other words, why aren't illegals that are caught in the desert arrested for endangering their children?
EXCELLENT question.