I could just throttle your h. No sense whatsoever.
You might want to check out the daycare and see just what is being paid. If your daughter isn't going there on his days, he might be getting a reduction...something just isn't right w/this deal.
When you sit the kids down, advise your son that if this happens again to call 911 and state that your daughter has run off and he doesn't know where she's gone and I would tell your daughter that the police will be called the next time she pulls such a stunt.
She's a very lucky little girl. There are so many children being snatched these days and it's just not safe for them to be out there alone, especially a little girl on the run.
I know you were scared and angry at the same time, but you don't want her to do this again.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.