House of Conflict — Mary Burchell

Alison and her cousin Lorna felt they had been very lucky to land themselves pleasant jobs as housekeepers to elderly Mrs. Storey and her family, in a beautiful house in the Lake District. Alison in particular hoped that now she might be able to trace Colin Marriott, who had walked so suddenly and mysteriously out of her life but whom she knew to be living somewhere nearby.

Find him she did, but to her mortification Colin explained -- quite kindly, however! -- that Alison was wasting her time in thinking of him seriously, and then proceeded to fall in love with Lorna.

But Alison had things other than Colic to worry about now, for she had gradually realized that not all the Storey family were as agreeable as they had at first seemed -- and that, in one of them, she had made a dangerous enemy.