Blover - thank you for your feedback.
Secondly, I purposely never identified person not to be named as a "she". If you got that impression, it was entirely through conjecture.
I think I presumed SHE based on "they MOTHER 3 children".

But definitely look into the RF products. They work, as long as the batteries are working and you're within range. But there is no substitute for training.
You could also consider concealing a key, even if a Valet key, under the vehicle in a spot difficult to identify but not extremely difficult to access.