Panel 1: We find ourselves watching Elizabeth grab a cereal box out of the cupboard. It might look as if we're about to watch her eat breakfast but we're not.
Panel 2: What we're watching instead is her shaking the box to see how much is in it.
Panel 3: The strip proper begins with Elly asking Liz why it is that she's brought down what looks like every box of cereal they have.
Panel 4: She tells Elly and Michael that most of the boxes only gots a little bit of cereal in'em.
Panel 5: Since this is obviously a pointless waste of real estate, she tells a baffled Elly that this is why she's putting them all in one box.
Panel 6: Since this obvious solution to pointless waste baffles the Hell out of Elly, she tells her it's a nice idea before trailing off.
Panel 7: Since Mike is a picky eater who can't stand the idea of a hybrid cereal and also since he lives to make Liz feel stupid, he asks who would ever eat this mess.
Panel 8: We cut to John eating the mixed cereal like it ain't no thing. This is meant to indicate that he's just this big slob who Elly can never make mature.
Summary: What it actually makes him is someone who ain't as fussy as Mike or as stupid as an Elly who just lets her kids eat just a little of each cereal until there's a whole lot of nearly empty cereal boxes gathering dust in her cupboards.