I thought it was obvious she was going to be the old man's daughter or granddaughter. If you couldn't tell from her eyes and facial features being a bit too clean, or the clothing, the mannerisms she has when addressing him in prior chapters were a clue.
It was still possible she was just an effeminate man, but that just got ruled out.
Honestly though, a possible second wife is something he needs in his life at this point.