Winds of Change by Jane Hatton
Kim and Tamsin met each other in Things that go Bump in the Night, each of them unaware at the time that they had ever had a twin, and by doing so inadvertently solved the mystery of who had killed their birth mother more than twenty years before. But the story didn't stop there: the consequences of their separation, of what had led to it in the first place and of what had subsequently come out of it, would have to be addressed, and this would involve new friends, new partners, and the start of new lives for them both, and the reunion of a disrupted family, the rescue of a near-derelict listed building and its adjacent farmland, and the restoration of a man's whole life. A West Country saga, and a delight to read.