Last night, Aidan called me urgently to the basement where he was on the computer. He excitedly showed me this youtube video laughing hysterically throughout. When I recovered from my own hysterical laughter, it occurred to me that this video perfectly symbolized the "pain" the oldest child must feel upon the arrival of a younger sibling. (My older sister can definitely confirm this.)
Compounding Aidan's pain, later there arrived yet another sibling. Of course, at about that time, the second child also experiences the displeasure of being displaced. This could explain why I once found Gunnar attempting to suffocate Brody with a pillow when he was a baby. While I have no specific memory of this, I am convinced that, at some point, my middle sister attempted to eliminate me as well.
Never leave a toddler alone with an infant.