It is probably nothing, but it is strange to find anything that looks like an explosive device in a family home.
Apparently there was some concerns about people coming into the house before they left. I remember a neighbour mentioning that he was asked to keep an eye out.
It could have been place there by someone to target the family, or to make him look like something else, or even as a defense if they thought someone was coming there to get something? I obviously do not know, but it is so bizarre!
I jusk keeep worying about the surviving girls, whoever was behind this attack has some serious resources. I am obviously very naive because I cannot understand what reason does one have to target a whole family including very young children.