Courts do not like to interfere in these situations with new boyfriends/girlfriends being around the children, but will do so if there is some evidence that the new friend is a danger to the children in some way or finds that the children being around the person is not in the best interest of the children. What would have to happen is that your ex would have to go to court to file a motion complaining that he does not want the children around this person and would have to provide specific evidence as to why. I would caution that if either of you are spending nights at each other's places with the children there, the courts may consider this and have ordered that it stops or they can change custody and visitation. Other than that, if it is merely dating and visits back and forth, there is generally nothing the court will do.
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