I didn't translate anything I just looked at the pictures.
I think Myungha got into a coma when he finally reunited with the prince. In his dream, he met with some kind of gods, they are really handsome. He came close to dying and as soon as he stopped breathing, the prince tried to kill himself but the baby inside Myungha saved him so he started breathing again. With the help of gods he met in the dream I supposed (?), Myungha woke up. He gave birth magically to a baby boy who looks just like the prince with the help of a shaman or god who is more powerful than sage Zhang, I think.
It's a happy ending and I don't know how, they get married in the end? With bridal clothes and everything but I could be wrong. The baby is really cute with prince clothes. Awwwnnn.










I don't know about the legal process in Korea. But, in my country, you can add someone to your family register and you will become a legally bind family under an official breadwinner family member. In this case, it's probably like Haebom is the breadwinner, the holder of the register, and Ho and Sol are under his register. It's not really adoption per se but it's still adopting I guess. You can add like "brother" and "daughter" under the "how this person related to the register holder" column. I don't know why Ho has to change his surname to Kwon. But this is a general idea.
Adoption in SK requires the adoptee to change surname ^^