here in New York state (the one in the USA as opposed to those in other countries) dual relationships are allowed. we have many many small towns where its not uncommon for people to grow up with each other, go to elementary, jr high, high school together, be friends go to college to become social workers, doctors, therapists, nurses, psychiatrists, psychologists then return to the small town to be that towns school nurse, school psychiatrist, psychologist, be that towns doctors, and such. so they end up having to be the treatment providers of their peers, friends, relatives. many NY towns are many miles, hours drive away from nearest cities, hospitals mental health care. the town I grew up in my best friend is the school nurse and town nurse, anther friend of mine is the school psychologist and the town community psychologist both of which have to not only treat the new folks that move there but also generations of friends, family and peers they grew up around.