This was fabulous. It gets 9 out of 10. What keeps it out of the 10 category is the fact that two big questions are raised in part 2 that part 3 (the conclusion) fails to answer.
First of all, what happens to the fifth sister, Cecilia? She first appears in part one as the late-in-life child of the second Duke of Richmond and his duchess. Still a baby when they die, she is sent to Ireland with Louisa and Sarah to be reared by Emily and her husband.
In part 2, the reappears as a teenager. When the family learns that Sarah, now married and back in England, is pregnant, she wants to go and help with the new baby. Emily is afraid that she is too weak to travel, having just recovered from an unspecified illness, but she lets her go anyway.
The next time we see her she looks very ill indeed, but nobody pays any attention. Emily has come to England to argue with Caroline about who should be blamed for Sarah's bad situation, with Louisa along to mediate. As they quarrel, Cecilia leaves the room, and we see what they miss: she's coughing up blood. When come into the hall, still shouting, they fail to notice that she has collapsed in a corridor.
So what happened??? That's the last we see or hear of Cecilia? Did she die? If so, didn't the sisters get back together at least for the funeral?
Maybe I need to read the book.
The other question is: since Sarah, at least as played by Jodhi May, seems to have lacked something in the personality department, how did she manage to inflame the passions of so many men?