Maybe he just needs a little guidance and someone to care about him. I would set firm limits for him discussed with him and explain to him why. Tell him he is spending so much time with your family that it is preventing him from doing the things he needs to do to be successful in life. Give him times (once a week for one hour for example at 4 pm on Thursdays) for a weekly visit and to catch up. Give him ideas on things he can do for himself to make his life better.

Please don't just throw him in the garbage. He is most likely infatuated with your daughter because her life looks like something he wants for himself.

Good luck with this situation.

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