As al_c notes in post #46, she woke one child and took him outside and killed him. Then woke the other child and did the same.
It seems like the husband was maybe not in the house at the time? Maybe out of town? I'm not exactly sure, but that is what I seem to recall from an earlier article.
Okay, thanks for the explanation about the kids. How awful for them. The article states that the father was sleeping.