Over 200 mothers in the United States kill their children every year.
Now that is a sobering statistic. I really don't understand killing your kids, at least not until they reach puberty.
I think it's just easier to leave them with family or neighbors and not come back. Sure, the grandparents, aunts and uncles, or neighbors are going to be pissed over it, but hey! It's better than killing them in the long run.
You can also drop your kids off at an emergency room or a fire station or police station and it's perfectly legal in a lot of states. In California, I think the upper age limit to drop kids off and relinquish custody is 27.
If you feel obliged to go through the old "somebody must have come in and grabbed that baby in the night while I was sleeping/drunk/watching a movie/having sex with my gay lover", then I think it would be better to take a page from the old "A Dingo Took My Baby" scenario.
The "dingo" substitute in the photo is my pit bull, Zoe. She has run off with a teddy bear actually, not a real baby. It really doesn't matter. When I go back outside in a few minutes the "baby" will be completely gone. There will not be a trace of it left.
Zoe ate almost an entire cactus. She also ate a remote control and a computer mouse. I think she also ate my husband Alex's "doo doo". Okay, that came out wrong. His "doo doo" is the plastic thing he used to shove into a slot on his laptop to activate the secure line on it. The "doo doo" is missing in action. Gone!
I still think leaving the kids off with the neighbors is a better idea.