A penguin of The Snares, an island cluster off the southern coast of New Zealand, these guys breeding range is limited only to those few islands. They typically lay two eggs, but the second is always largest, and one of the siblings is usually killed in competing with the other for survival. This practice is known as ‘siblicide’.
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Clowderthing_Mryarra
He's definitely got the look of someone who killed their sibling as a child.