I'm going to say this now, but it applies to both this chapter and Chapter 8: Sam and Zoe are children whose father died in the last month, and now as far as they can tell, they've lost their mother and are being told that a man they've never met is their new parent. That's traumatic, and while I'm not going to say that either of their behavior is ideal, this is a story without villains, and from my perspective, neither of them is doing anything wrong - they're just handling their trauma the best they can with the resources they have at hand, and those resources are not sufficient.