You need to be advised by a licensed MN family lawyer. You aren't giving enough information to answer the question. You need to act quickly because there may be limitations on the amount of time you have to enforce your rights.
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You should get the assistance of an attorney. There are many details that would need to be addressed. If either the birth mother or her husband have a criminal record, that could be a complicating factor that would need to be addressed with the court. But, as a general matter, yes, this could be accomplished. You should schedule a free consultation with an attorney.
The short answer is "maybe." Like the others have said, it is possible, but there are factors and circumstances that could work to either complicate the process or thwart it all together. Most attorneys offer a free, no obligation consultation. You should contact an attorney in your local area and discuss this matter with them.