It is what soldiers of the Pewdiepie army are called. They were previously called as Bros, Sisters, Sister Sqaud, Squad and are now 9 year olds. True 9 year olds are those who did their part, such as Mr.Beast. Do your part, and subscribe to pewdiepie
The 9 year olds pledge their loyalty to the Lord Pewdiepie.

The 9 year olds suffered casualties in the T Series war

My friend Imag Ayman enrolled in elementary school to become a 9 year Old
by Brief Velkoz December 5, 2018
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If it's a 9-year-old, it's subscribed to PewDiePie.
I've got 9-year-olds of worlds so hold your defecation.
by SociopathicDuck January 1, 2019
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What Pewdiepie calls his fans.

History:
PewDiePie uploaded a reaction video, Alinity made a response video (I can’t call it an apology video just because), and that video was reviewed by PewDiePie. Alinity mentions PewDiePie having 9-Year Olds as his fanbase.
Alex: Hey, Cam. I've you calling your friends' 9-year old.
Cam: yeah.
Alex: What's that supposed to mean?
Cam: It means that you aren't one, even tho you should be. subscribe to pewdiepie
by Gllllow January 14, 2019
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Fans/subscribers of Pewdiepie
Anyone who watches Pewdiepie, regardless of their age, is referred to as a 9-year-old.
"I love my 9-year-olds!" -Pewdiepie
"If you're subscribed, you're an actual 9-year-old."
by RealGodsSub2Pewdpiepie February 8, 2019
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A boy who plays Call of Duty and tells his mom to bring him energy drinks, then cussing her out for bringing him Red Bull instead of Monster, then cussing you out incorrectly for shooting him.
9 year old:You brung me Red Bull! Hey punk you shot me you turd! GET WRECKED!!!!
by Cracka531 May 22, 2014
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