The old inn welcomes and protects the whole family, including eventually Nadine herself (she just has to accept and surrender, like she did in the last book) and the two mysterious newcomers, Annie-Laurie and Malony, who are hiding some very dark secrets. I do feel for Nadine, the mother figure, who has sacrificed so much for a life that she doesn't really enjoy. I would love to see her have some outlet for her creativity beyond beautifully decorating the rooms and being a perfect hostess! (She does gain some fulfilment in her friendship with Annie-Laurie, but still.)
I think I've worked out why the Eliot Family trilogy is so peaceful to read -- there is no action at all! Almost every scene is someone thinking about their life, or people talking to each other, usually in a beautiful woodland setting or a lovely old room, described in minute detail. The drama comes from the interaction of different personalities or from an inner struggle. Even Annie-Laurie's very dramatic backstory is given to us in conversation, in retrospect. I don't say this in a disparaging way, it is a real gift to carry a whole novel (let alone a trilogy) without leaning on action and plot, and it's clear that these novels are much loved and often returned to. They are meditative to read and spiritually refreshing, a great source of comfort and strength for many readers, including me.