I thought of posting this under "Academic guidance," then decided to post here. This friend of mine (I'll call him Jack) has a female friend (Holly) who lives in Europe and whose college-age daughter, Emma, is a freshman in a major U.S. college. Holly asked Jack to check on Emma once in a while. Emma visits Jack's family during holidays; they converse and have food together. Jack told me that in her last visit Emma told him that she has been going out with her TA. Jack asked for my advice as to what, if anything, would be the appropriate action for him. He could: (a) say or do nothing, (b) tell Emma "she should have thought twice before going out with her TA," or (c) alert Emma's mother to the fact. Options (b) and (c) could imply infringement of Emma's privacy, and trust. Option (a) could potentially mean turning a blind eye to the possibility of Emma's involvement in similar relationships in the future. What do you think is the appropriate action for Jack?