I missed this somehow, but I'm confused about Rachel's mom. Was Rachel the oldest and her mother married Paul as a means to an end, or did she have an affair mid-marriage? Rachel didn't appear to be the oldest in my opinion.
shareI’m thinking Mr. Will and Rachel were twins.
shareI'm pretty sure that Mr. Will is not blood related to them. In colonial America, young men of adolescent and post-adolescent age were taken into families as sort of a apprentice. It makes Paul the master of Mr Will. However, in these arrangements, the young man 'belonged' to the master in many ways, and were accepted into the family as if they were family themselves. Their teacher becomes their father, and their teachers family becomes their respective family too.
There are many of these religious cults/communities like the Amish and LDS who are stuck in time in many respects, and in some of them this type of apprenticeship is still practised. That's why he was called Mr. Will, not just Will. Because he wasn't blood family, he was a student. But he was accepted into the family as if her was blood.
I still believe that peace and plenty and happiness can be worked out some way. I am a fool.