If you are married then likely your husband will be considered the legal father and not this other man. However, the other man can file a petition to establish his paternity rights and a DNA test may or may not be ordered. There is a consent and waiver a parent can file to agree to a step-parent adoption, but considering your husband is not the step-parent it may be unnecessary. You should consult with an attorney.
This is not to be considered legal advice nor does an attorney-client relationship exist.
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