When the parents are separated/divorced and one parent has their child sleeping in the same room as a different sex step-child, the other parent may well find that highly objectionable and seek a court order to prohibit that. While it is not illegal (i.e. not a crime) for the parent to room the kids together, when the matter is brought to the court the the judge is faced with having to decide the controversy, and the standard used is the best interests of the child. In making that decision, the judge will look at everything and the rooming situation is certainly one the court may take into account when deciding the issue. So it is not quite correct to say that a court would never care about this unless there is some history of abuse/inappropriate behavior going on. In some cases the court may well determine the arrangement is not in the child’s best interest and enter an order to address it. The totality of the circumstances matter. My point in this thread is that the apparent implication by some that it is never appropriate to have different sex teens room together and that a court will always prohibit it is also not true. Again, the totality of the circumstances matters. Like it nor not, once the parents drag the matter into court, the judge is faced with having to decide between two conflicting views of what is appropriate for the child and the judge will have to care about all the circumstances that affect the child.