You cannot do a grave wrong in hopes of making something right. Even if the mother was risking her life by continuing the pregnancy, the reality is that there was not 100% risk of death for the mother but the abortion was a 100% risk of death for the baby.

If this is a real scenario then of course the children are angry. I used to date a boy whose mom died in childbirth. She'd had six kids and there was no reason to believe she would die giving birth to the seventh. THe kids were STILL resentful of their little sister and they were in their late teens. Frankly kids are mad at their parents who die even if it's in something besides childbirth. It's the result of immaturity and fear of abandonment.

I still don't see how you could justify the abortion so maybe you can present the argument more clearly. A couple of angry kids is hardly a reason to kill someone
Lisa N