i think it is odd that a) a family member called to voice concerns, and Mom still was alone with the kids and b) that Dad echoed the concerns of the caller but allowed mom to be alone with the kids.
2 people noticed she Maybe could harm the kids but did not watch her like a hawk, as i would have.
Oh well maybe they are very young people.
Lots of people hesitate to do the right thing now for fear of "invading someone else's space".
I think they couldn’t find her then couldn’t find the kids.