What you have to do is box clever between the parents, our kids think we know nothing ... I beg to differ we have an inter family call / text thing going on. Most parents would be relieved to know that you are all as anxious as each other. I have been on search and find missions in the early hours of the morning with mates but like the Mounties ... we always get out man! lol. Once we knew where they were - they had tried the I'm staying at ... all say one other person ... ruse, we had a plan b - they were safe ... but they had no idea ... they were freezing and scared poo- less when they returned home before 9 the next morning. If they had really been sleeping over they would have been happy warm comfy and sleeping late - the best lesson they got was being scared, freezing going to the loo in a petrol station, and so unhappy staying out in dubious circumstances - not able to lose face calling home ... and all the parents sent night night love you texts ... they didn't do it again they were fourteen and fifteen at the time.