Okay kiddo, do you know what a felony is? It's something very bad that people do like robbing a bank or hurting someone. And sometimes, when people do a felony, something really bad happens by accident, like someone gets hurt or dies. This is where the felony murder rule comes in.
The felony murder rule says that if someone does a bad thing like a felony, and someone gets hurt or dies because of it, everyone who was involved in the bad thing can be charged with murder even if they didn't mean for anyone to get hurt or die.
Let's say there are three people named Jack, Jill, and John. They decide to rob a bank but they didn't plan on hurting anyone. However, while they were robbing the bank, Jill accidentally shoots and kills a bank teller. Even though Jack and John didn't mean for anyone to get hurt or die, they can still be charged with murder because they were with Jill during the robbery which was a felony.
It might seem kind of unfair, but it's a rule that's meant to make people think twice before doing a felony because it's not just about the felony itself, but also the possible consequences that could happen.