We had an interesting one this weekend.
One of ours has started going into town and leaving his mobile phone switched off, which means we can't track him.
What did parents do before Apps like Find My Phone and Find Friends?
We used to sit at home twiddling our thumbs worrying our socks off about where they were and who they were with and what they were doing.
Then, suddenly, you get them a mobile phone - which they are desperate for - install a tracking app and blimey, you can tell which shop they are outside or which friends house they are at to within three feet. Brilliant!
But obviously, it's not what they want. Not what I'd have wanted as a child. Big Brother watching your every move.
The whole point about growing up is getting away from the apron strings. Learning to stand on your own two feet.
There's even more to it than that; it's about freedom. The sheer exhilaration of being away from parental gaze, the rush of knowing that there's no-one zeroing in on you. In fact, it's a hell of a buzz to realise that the main person looking after you is...you yourself.
So we, as parents and foster parents have to let this happen, stage by stage.
And it's agony.
Not because your little ones are flying the nest, or at least beginning the process that will result in their departure, but because we worry.
By God don't we worry when we don't know where they are, the first few times.
Actually, not just the first few times, we worry about them all the time when they are out of sight, no matter how old they are.
Now, getting back to the one who's deliberately switching off his mobile so we can't see where he is.
We let him.
It's one of those fine edged judgements which in fostering come at you thick and fast.
In his case, we decided he is broadly speaking responsible enough to behave wisely. So far so good. He doesn't want to be the only one of his friends who is being tracked. In fact, we tend not to call him or text him because, again, it's embarrassing if his phone goes off and it's the bloomin' parents checking up on him.
Here's the bonus; he knows that we are giving him this slack, and he's quietly grateful, respectful even that we are showing him this much respect.
So job done.
Mind, I'd still sooner know where he is. Save me standing at the living room window watching out for him coming home, and then, when he appears, ducking out of sight so he doesn't realise I've been worried sick.