It is difficult and in any conversation where there may be a presumption of confidentiality I would always try to reserve the right to speak out if, in my considered judgement, I felt it was necessary. In my experience (which in this area is quite a lot with Godchildren/foster children esp.) I would usually thank them for trusting me with whatever the information is and then try to lead them to a point where they can open up the discussion with a parent or another appropriate adult. I usually say something along the lines of; 'you've trusted me this far, now trust me to help you with the next steps'. In this way I try to avoid breaking a confidence, but I have had to engage in some serious negotiation at times to ensure that a young person's safety isn't being compromised and at the end of the day that's the job of the adult in the situations you describe. Safety trumps confidentiality, but helping a young person to feel okay about discussing big issues is really important and often needs 'processing' time on their part.
Fruit flies - help needed please.
Army horses loose on London streets
Have any of you got all electric cars? Pros and cons please.