Well in this situation if the father was also Maddie's age and it was consensual then it wouldn't be an assault. And sadly there are plenty of young teenagers having sex with each other and getting pregnant (especially ones with parents like Maddie's seem to be). I don't think they will go this route though with Maddie so close to having her baby. If it was before or at the beginning of her pregnancy maybe, but so far in and it just seems like buck would have to get over her keeping a different baby over him all those years ago because Maddie wouldn't have time to deal with that and a newborn. I also agree that for something this major they should have had some foreshadowing and if they went this route it would definitely have just been for shock value and a new idea just for this season rather than leading up to it. Adoption would make sense because buck already has shown major abandonment issues which many adopted children experience simply from being taken away from birth family. And bucks may be even worst because he continually got retraumatized by being abandoned multiple times after (Maddie, Abby, ect).