The weekly holiday of calling your siblings on Sunday, no matter how far from one another, or not close you are to one another, simply to keep a connection, and possibly strengthen your lineage in case of a "Game of Thrones" and /or "Succession" scenario.
My sister told me about the subway bum that attacked her this week when I called her on Sibling Sunday
This Sibling Sunday we talked about gathering board seats to vote our father out as CEO
It was great to talk to my sister on Sibling Sunday this week, I cant remember the last time our mom talked to her brother.
My sister called me for Sibling Sunday and was disgusted with how hungover I was but still had a great talk.

Sibling Sunday is the best cause no matter how successful your sibling is they wont judge you
by GeorgetheGypsy January 18, 2023
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Like man crush Monday or women crush Wednesday except for siblings, meant more as a joke because you should love your siblings, or just not hate them
by Sam-nugget June 28, 2017
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As we all know WCW or MCM we now have SSS (Sweet Sibling Sunday). This is a day where you post your siblings high or low, goofy or not... we dedicate this day to our siblings :)
SSS to my bro bro

Sweet Sibling Sunday (SSS)😁 to my sis... I hate you
by Clingyness I diss October 18, 2020
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