(Strip Number 4183, Original Publication Date, 9 June 2011)
Panel 1: It would seem that Elly's need to sort of not reassure Mike as to the whole 'favoritism' thing has once again added to his raging paranoia about being replaced; that's because we find him thought-bubbling "Sisters! They're a pain in the neck!" as he kicks Lizzie's toy bunny out of frustration and/or malice.
Panel 2: He then thought-bubbles why it is that Lizzie annoys him: "Always whinin', always gettin' their own way!"; given that what she's whinin' about is his being a looming menace that swoops down and taunts her out of self-absorbed malice and what she gets away with is defending herself against his mindless, vicious aggression, I find myself somewhat unsympathetic to his plight.
Panel 3: He then seals the deal on my not caring what the crap he thinks by saying to himself "If they had to have another kid, why, WHY, couldn't they give me a kid brother instead."
Panel 4: Having spent most of my childhood getting into a spot of bother with my older brothers, his telling himself that everybody knows that brothers don't fight puts the final nail in the coffin of giving a rat's ass what he thinks or wants. He's as stupid, ignorant, mean and stubborn as his worthless father.
Summary: In case anyone still wants to defend Lynn's warped point of view, the notes that will inevitably condemn her parents for not giving birth to the kid sister she'd probably have hated far worse than she does Alan will probably help cure that.