the one who's at fault here is the fl she act strong but she's so arrogant even when they first met with the duke, and the duke just wants to take responsibilty for what happened 5 years ago and plus he thought the kid is his child because they look alike, besides this sh** and fl doesnt have any marital relationship they only a partnership in business so the duke can do what ever he wants and that sh** doesnt have any rights to stop him because he's not the fl's husband or boyfriend. 
./.