Does anyone remember the name of this children's book?

I remember reading this really messed up children's book in grades 2 or 3, I'm 25 now so we're talking early 90's. I just remember a brief synopsis so if anyone knows the name of this book please tell me!

All I remember is a couple gives their children to a family of giants for some reason I don't remember. So living in the house are the giants, their 3 children and the 3 children that aren't theirs. So the mother gives her own kids silver necklaces and the others bronze necklaces so she can identify them easily at night cause she wants to kill the other kids for a reason I'm forgetting. But the oldest of the 3 children what are going to get beaten to death hears this and switches the necklaces. So the wife ends up putting her own kids in a sack and beating them to death.

That's all I remember but I know for sure I read it because I remember the pictures so vividly. Please help if you can, thank you!

 

The story is quite interesting, but with this hint its really difficult to find the title of the story. In starting its matching up with the story of Cindrella. But I know this is not the same story. You will get to know soon, :2thumbsup: