First, if it's your fiance's child, he's not yet your step-son. Second, you have no rights to visitation/see him because you are not his parent or have any other legal relationship to the child. The father should seek a court order granting custody and visitation. Hire a local family law attorney asap.
This is not legal advice nor does it create an attorney-client relationship. This is for education and informational purposes only. It is always recommended that you contact an attorney with any concerns as each individual case is unique.
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