It does happen.
My wife’s former best friend, her father just got out of prison for violating parole. He got wasted in Austin, fell down some stairs, and ended up passed out all beat up along the curb. When the cops found him, he claimed he was beaten and robbed by some black kid. He gave a description and they arrested someone. It wasn’t until the investigation went deeper that they realized what was going on and he finally fessed up to it under interrogation. I wish I was joking or making this up. There may even be news reports floating around about it as it happened either last year or the year before.
Regarding the story, I did find it odd that she had a life insurance policy on her child. I have an almost 2 year old child and we never even considered it. I did a poll of friends and family and only one out of 10 had it and they are in more of the upper income bracket (dad is a finacial planner). He told me that most people, especially in the middle to low income, dont have life insurance on their kids. If any, usually dad carries it.
Considering the rest of the evidence, I doubt the mom did it and the perp isnt even claiming she hired or put him up to it which would fit the typical life insurance death scenario.
I know many people who have small policies on their children.
For one thing if your child has health problems it guarantees them the ability to get a policy once they turn 18. Lots of variables of course but the policy is not that unusual, IMO.