And I'm wrong; it's Elly expressing exasperation because nobody appreciates the sacrifices she makes.
Panel 1: We start off with John asking a howling Lizzie, who's holding up her beloved toy bunny, what the trouble is. This is a fairly nice thing to see because it reminds us that once we get him to quit cowering behind his paper, he can be a fairly decent parent.
Panel 2: Having realized that there's something about the buuny that troubles her, he asks "Your bunny? What's the matter with your bunny?"
Panel 3: He then asks Elly what's wrong with Lizzie's bunny.
Panel 4: Elly, with her face locked in an annoyed, put-upon scowl, says that she washed it.
Summary: If I didn't know these people, I'd think that this was an ordinary event: Baby doesn't recgonize the toy in its original state and over-reacts which makes Mom slightly ticked-off because she didn't see that coming. The fact that Elly is like this all the time tends to spoil the moment.