"There... are some theories that it was less innocent. Here is where theory mixes with what is said outright. But it is accepted by a number of fans that Chara... had been abused by their human family, and that they fell down Mount Ebott in a suicide attempt. And that Chara... knew that the plan would mean that Asriel would have to kill a number of humans to break the shield, and that the mistake wasn't failing to understand the consequences of dead humans but failing to understand that it wasn't in Asriel to kill people. Asriel failed to understand that as well for what it is worth. And ironically... after death that hesitation to kill would... vanish. Neither child gets to just rest after death and... things get dark. Very dark. And given it tarted with child abuse and an attempt at suicide... I feel obligated to give a trigger warning before I continue."