A 16-year old can indeed be arrested with or without any parents present. It is irrelevant if there is a parent present or not. The only issue is whether the police: 1) had an arrest warrant, or 2)...
you son/daughter is 16 and the person s/he is seeing is 18. i don't see a problem with this. i can understand that you still see them as your little girl/boy but s/he is stating to grow up and i know...