Thank you. Okay, I understand that the 18 year old (who has engaged in sexual activity) and the 17 year old are not under a guardianship order from the Court.
At this point, the client that has engaged in sexual activity is an adult. Someone in your situation cannot tell their parents about this (or, should not) because this may be a violation of their privacy (false light, invasion of privacy), unless the POA signed by the 18 year old specifically allows you to share such information with their parents.
It is the business' discretion whether or not to mention this to the 17 year old's parents. The problem here is that if there are only 2 people living there, by mentioning a general risk, the inference would be immediately made to the 18 year old as being the one with the STD - again a violation of their privacy and may be cause for suit (false light, invasion of privacy, etc). As such, this is at the business' discretion. It may be simply better to advise the 17 year old's parents that there is a "risk," but explain that due to privacy issues, nothing more can be said (so as not to inference the STD to the 18 year old, directly).
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