If your daughter is now 18 then she is no longer a minor for custody purposes and she can make her own decisions regarding custody. Based on what you stated above it appears that you are in contact with her and did hve plans to see her. Since she lives with her father, he does have responsibily in the sense that he is caring for her while she is living with him but she can make her own decisions on who she wants to see since she is no longer a minor. I would suggest try talking to the father in order to avoid conflit for everyone, if possible.
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