In Massachusetts there is no clear cut answer on how to deal with this difficult situation and the answer generally lies with each individual judge.  The only guidance a judge has in this situation in Massachusetts is our “best interest of the children” standard.  I would also suggest to parents confronting this situation to use this standard as well.  Before you act, stop and think about what is your children’s best interest.  This isn’t to suggest that unrelated third party visitors (a term that courts use for a wide variety of individuals that are not directly related to the parties and the children) are always a bad idea, however, courts do take a cautious approach.  My experience has been that courts are very wary of exposing children to this often awkward and confusing situation.  The age of the children also seems to play a significant role; the younger the child(ren) the less likely a court is going to allow any sort of contact or even consider the even more delicate issue of “sleeping over.”