Samuel Beauchamp's Mother
In "Go Down, Moses" and again in the chapter with that name in Go Down, Moses, Samuel Beauchamp's unnamed mother was the oldest daughter of Lucas and Mollie Beauchamp; she dies while giving birth to him. In "A Point of Law," Lucas and Molly Beauchamp have at least one child besides Nat; we are assuming this child is the daughter who gives birth to Samuel, though the story's only reference to her is ambiguous. According to the narrator, it is known that Lucas has "one daughter with grandchildren" (214). Since this is mentioned in context with Lucas' age, it's possible that the "grandchildren" are his daughter's, making Lucas himself a great-grandfather, but no other details or family members are mentioned - and it's more likely that the phrase means Lucas himself has a daughter and grandchildren, which is the way we've chosen to interpret it.