SOLVED. Mystery novel where two people are murdered from being thrown off a balcony and one is found in a trunk

[Maryum]

I thought it was a Agatha Christie novel with Miss Marple, but I've looked through all the plots and I can't find it. I thought I read it within the last couple of months, it's set in the 50's, I think. It starts with this young woman going off to be a maid in a country house with her 5 year old niece. Her "boyfriend" who is a policeman asks her not to go because the house has had issues. The owner of the house invites Miss Marple down to stay and she masquerades as a friend of one of his aunts. Miss Marple tell the owner of the house to make an announcement that he won't sell the house, but he refuses and the next day he's thrown off the balcony. In the course of the book the butler is also thrown off the balcony. There's a weird subplot with one of the men of the house having impregnated the butler's daughter and that same man having jilted the next door neighbor. The next door neighbor gets together with the current owner of the house who was an invalid and *spoiler* it turns out the nurse who was taking care of him murdered the one of the men of the house and left him in a trunk in the basement and she threw the other two men off of the basement. She ends up getting away but Miss Marple tells the police how to look for her. And uncharacteristically the two characters in love, don't get together. I really thought this was a Christie novel!

[Maryum]

I remembered the book, it's Pilgrim's Rest
It's a Miss Silver mystery by Patricia Wentworth