National oldest sibling day is a day to be thankful for the oldest sibling for basically being a 3rd parent, they sacrificed many things for the young ones, and most of all, get yelled at the most.

National oldest sibling day takes place on July 15th
Guy 1: I hate my older brother!
Guy 2: Be nice bro! It’s national oldest sibling day
by abiban74 October 16, 2019
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