I can remember the plot, but not the name of the book or the author, and it's really bugging me.
The central character is a house sitter, she's middle aged and has no close family. She takes up residence in a grand house which is mostly locked up, but she finds the keys and lets herself into the rest of the house. A young women with a baby turns up, the baby may not be hers, then a young man turns up. I can't remember if he has a prior connection to the young woman not. The group form a kind of family, but their days are numbered by the imminent return of the owners of the house. It all ends badly, blackberry pie may be involved.
I also think there may have been a TV version with the wonderful Penelope Wilton in the central role.
Can anyone put me out of my misery and tell me what it is?