Why would you want to put yourself in another family's dispute?
What if the mother (your former girlfriend) says that the stuff is legally hers? If you give the mother's stuff away, you may have to pay her money to compensate her.
What you can and should do is to tell the mother and father to take each other to court and let the court determine whose stuff it is.
It sounds as if you and the mother are still living in the same place although in different rooms. Depending on the situation, one or both of you may have to move out.
You should review the specific facts with your attorney to find out your legal options.
I understand that you may care very much about your ex-girlfriend's daughter, but this particular dispute is not yours. Your best course of action is to "stay out of it" all together. Both your ex girlfriend and her "ex" should be sorting this out in Court, and should be putting their daughter's interests first.
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