Whoever wrote this is a crazy person incapable of basic writing skills:
Mrs Johnson's gossip to Laura Collins about Peter Guthrie made Laura aware of Guthrie's plan to stop her and Laura killed him. Indirectly, Mrs Johnson is responsible for Guthrie's death. If not for her sneaky gossip, Laura would not have found out about his plan so fast. Mrs Johnson's nagging also indirectly caused Cassandra's hand to slip as she held a pin over a doll that affected Eric Lang's health. When Johnson came in screeching that she was not going to stand for something or other, Cassandra's hand slipped and the pin went through the doll's heart, causing Eric Lang to have a heart attack and die. Mrs Johnson was complaining about not having to make breakfast for Roger and Cassandra any time they want, different times from the rest of the family. And, thanks to that, Eric is dead.
Ahh ... blaming Eric Lang's death on poor Mrs. Johnson? NightBear