that one sibling that only leaves their room for food, but when they come out they're a total pain. you only get along with them when your being mean to some else otherwise you can't say a word to them without them getting mad or angry.
Latashia is def the toxic sibling, she comes out of her room, asks me what's up then yells at me to shut up.
by baldgirl February 4, 2021

A song from the FNF mod "FNF: Pibby Apocalypse" features Finn and Jake from Adventure Time, corrupted by the darkness from Learning with Pibby.
Person 1: "Yo dude did you listen to Suffering Siblings? That shit goes hard!"
Person 2: "Meh, Come Along with Me better."
Person 2: "Meh, Come Along with Me better."
by mugsarecool November 6, 2023

by Midnightcoff September 23, 2021

Any siblings or half siblings to you or anyone else in a sibling web. May or may not be related to you.
by Lexus14blacklist July 13, 2015

Person 1: Man, you’re an idiot.
Person 2: You’re an idiot!
Person 3: Bro, did they just use the sibling response? So lame!
Person 2: You’re an idiot!
Person 3: Bro, did they just use the sibling response? So lame!
by mp444 April 3, 2023

when one sibling is favored over another. most of the time it is the younger sibling is favored over the older sibling
(A is the older sibling and Y is the younger sibling)
hey A why did you break this jar!?!?!?
A: but mom i want even in this room!?
A i don't care!
Y: but mom i did it
Mom: ohhhhh
A: mom this is sibling inequality
hey A why did you break this jar!?!?!?
A: but mom i want even in this room!?
A i don't care!
Y: but mom i did it
Mom: ohhhhh
A: mom this is sibling inequality
by whyistheoldersiblinglovedmore January 22, 2014

A sibling that is born to give their organs, bone marrow, and basically anything that can be used to save the sibling that was born before from a terminal ill ness
So basically they’re trying to save one kid by using the other and a lot of it is not consented by the donor sibling it’s self
So basically they’re trying to save one kid by using the other and a lot of it is not consented by the donor sibling it’s self
by Wisper and crispy February 3, 2020
