Because she has just knocked on my front door to ask me "do you know your daughters are on their own out here?"
She had a face like this 
My DDs are 7.11 and 4.6. They are playing out the front of our house on the grass.
They have a little blanket to sit on and are threading bits of grass and daisies into a piece of cloth.
My front door and kitchen window is open...I am sitting where..I can moreor less see them....and I can definitely hear them and they and I check in regularly...the house is in a cul de sac...very quiet and both DDs know not to go near the road or they'll never be allowed out there again.
I KNOW it's 8.00pm but it's Saturday and very light too...they're quiet and happy and what's more, DH is working on the fence in the garden and regularly comes onto the driveway to get the tools he as out there..he's painting the panels.
We're not being loud or anything.
I said "Yes thank you I know they're out here" and looked at her blankly...she kind of went "Oh rght...but....oh never mind!" and waked off.
AM I wrong to let them out there in this way?