My first thought that differs from most of these theories is that William and Margaret’s baby was born during “Isn’t it a Lovely Night?” The previous song expresses the love and happiness that they both share with each other and it seems redundant to me that they would again express these feelings in two consecutive songs… unless, of course, something wonderful and life changing occurred, such as their baby being born. If this is the case, then it follows that when the Rake kidnapped Margaret, he left the baby abandoned in the forest where William and Margaret had made their little love nest. This supports the idea of the story being cyclical; a baby abandoned in the woods seemingly destined to be “rescued” by the Queen. This also, as a response to Kya in an earlier comment, gives William and Margaret an incentive to cross Annan Water again, to try to get back to their baby. This makes sense to me from what I understand, but Kya brings up the good point that the lyrics in the last song indicate Margaret as being in a state of mourning and having already taken measures for a sort of funeral. Unfortunately, the first six lines of “Hazards of Love 4 (The Drowned)” are quite incomprehensible to me.
My second thought involves simply the location of William during “The Wanting Comes in Waves/Repaid” It seems to me that after “Isn’t it a Lovely Night?” the rest of the events in the story happens in the span of one night, the last night for William to be free of the Queen before she takes him forever. The Queen catches William with Margaret and gets furious, but William bargains with her then and there because he needs to be with Margaret and the new born baby on the night of the birth. This is another reason why I think the baby is born on that night; it seemed strange to me that William would risk it all so blatantly to spend a random night with Margaret. If the baby was not in the picture, it seems more like that William would bide his time and wait for the opportune moment to run off with Margaret, instead of pleading to his mom to let him spend one night. The birth of his child, however, in addition to being caught in the act, would give William enough incentive to lie to his mother’s face and plead for just one more night in exchange for a life of servitude.

Well, there it is! If you took the time to read, thank you sooo much, I really appreciate it. And thanks to the person who wrote this explanation in the first place for giving me this opportunity to share my ideas about something I’ve come to love.

However it is nice to have at least one happy conclusion to be left with, considering the heart-wrenching ending.