agressive pregnant dogs

Question
Why would our one pregnant female golden retriever kill our other female goldens puppy.  she  picked the puppy and had it in her mouth biting it and killed it.  i have heard of males doing that but the our male golden is awsome and loves the babies.  I am wondering if she is going to kill her own puppys.

Answer
Some bitches have been known to kill their own puppies, but there is no way to predict if she will do that. I certainly would keep a close eye on her, and probably not breed her in the future or allow her around other puppies.

In wolves, usually only the alpha pair have offspring, as any other puppies in the pack are often killed by the alpha female. This could be something like that if she is the dominant bitch in the house.