This isn't tragic! This is criminal! I cannot believe anyone with half a brain would not miss 2 children from 9 am until 2 pm. Where did she think the children were? If someone else would have brought them into the house - wouldn't she have seen them? It says, "when she came back" - back from where? - she's running a day care and she's not there. I'm outraged!
I got the impression she had the boys in the car as she drove to work (which happens to be a daycare). Instead of taking them inside with her (?!), she left them in the car. Her story seems to be that she thought her husband was going to show up shortly thereafter, retrieve the boys from the car, and take them with him.
In other words, she claims she was using the car (and car seats?) as a temporary holding cell for the two little boys, ages 3 and 5.