Nicaraguan Sibling Surprise

Two toddler siblings take a shared bath. While one contentedly entertains himself, the other stands up behind him and urinates on him.

I only turned my back for a second; when I turned around Manual had initiated a Nicaraguan Sibling Surprise on Isabella. She lucky that he only peed on her back.

by Crack Jacky September 2, 2009

Eldest sibling syndrome

Eldest sibling syndrome or E.S.S is When you are the eldest amongst your siblings so you automatically fall into the cycle of having to use things until they are disintegrating because you can't ask for new ones.

Whereas on the other hand any younger sibling can ask for whatever and get it instantaneously because they are not the eldest.

Examples of this include tattered clothes and using things until they break.

Person 1: Dude. Your underwear is literally hanging by the elastics. Why don't you get new ones?

Person 2: Oh you know why. Ask my little brother.

Person 1: No wait. Don't tell me you have Eldest Sibling Syndrome!?
Person 2: It's gotten worse

by Mad King JJ July 29, 2017

full sibling

Person who has the same two parents in common with someone.

My full sibling is a good person.

by Mr. Jacov November 23, 2019

half-sibling-in-law

Spouse's half-sibling or half-sibling's spouse.

My half-sibling-in-law is a good person.

by Rwopazaq November 24, 2019

double-sibling-in-law

Sibling’s spouse and spouse’s sibling at the same time.

My double-sibling-in-law is a good person.

by Rwopazaq November 24, 2019

co-sibling-in-law

The spouse of one's spouse's sibling.

My co-sibling-in-law is a good person.

by Elivaldeq November 24, 2019

forced sibling

A sibling under your age who you didn’t ask for to be born or your parents had without asking you.

Melissa: Kaylee has a forced sibling, how sad.
Jessica: I bet her parents don't care about her anymore.

by Yuhh :< June 11, 2020