Episode of the wandering knife; three mystery tales

I am a real Mary Roberts Rinehart fan. I'm 54 years old and when I was a kid -- around 10 or 11 -- I first discovered her. I've always enjoyed a good mystery and likeable characters and this author has never disappointed me. Ironically, MRR's mysteries (all of them) are almost historical in concept. Back before the depression, there were people who actually lived like this. Reading one of these stories is like reading a little bit of history. In this particular book there is a widowed mother (wealthy), a daughter, a brother, a daughter/sister-in-law, various servants and side characters. The book is told from the point of view of the daughter and starts off with a big party thrown by the mother for her society friends (including the mayor). The daughter-in-law is found murdered after the party and the husband/brother is immediately suspected. The mother finds the murder weapon, hides it, and gives it to the daughter who really believes her brother innocent and wants to protect him. The story is engaging, entertaining. I's been a while since I read this and for a minute I couldn't remember who-dunnit!! Not that it matters, because with MRR it's not (in my opinion) who was it who committed the crime, but the journey involved in getting there. And periodically I'll go back and re-read these books just for the fun of reliving them all over again.