The case of the child father and the adult mother takes murky to the opaque. A boy can't be held responsible in the same manner as a man, but there is still a child to consider. Remember him? Now is the time for Solomonic wisdom. We wait for the boy to become man, then we give him the man's responsibilities. I think that works out well for all of us.
If that's your idea of 'Solomonic wisdom', I truly hope Solomonic wisdom is nowhere to be found in any society.
If a 14 year old girl had been raped by a 20 year old man, would you wait until she was 18, and the start charging her child support? If you say 'yes', that's a grossly deranged opinion but at least not hypocritical. If you say 'no', your stance on holding raped boys responsible but not raped girls is hypocritical and grossly deranged.
There are a lot of deranged opinions in this thread and this one hardly stands out. It was Solomonic wisdom that was concerned with the welfare of the baby. Somebody is going to get a raw deal out of this situation. Solomon says it's not going to be the baby. Others have more sympathy for the former 14 year old. There's arguments on both sides.