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
by whyistheoldersiblinglovedmore January 21, 2014
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