My sons biological father has never tried nor seen his 7 year old son. After multiple attempts of reaching out to him he wants to now get secondary custody and visitation after going after him for child support. Does he have a chance of getting ligitimation? Can it be an option for his step dad to adopt and drop child support?
We need to know what state you are in. Each state's laws are a little different. However, if you are in Georgia (which is the only US state that has legitimization) Then yes, he can get that. He can also get secondary custody and visitation. He might have to jump through some hoops to do so, and have some joint counseling with the child and some phasing in, but he can get all of that.
If your current husband really wants to adopt the child and the biological father is willing to go along with that its possible. However, that means that your husband will be the full, legal father of your child, forever, and will be just as able as you to get custody and child support should your marriage fail some time down the road.