New sibling syndrome

When children who have recently acquired a younger sibling feel so excluded that they pretend the new member of the family simply doesn't exist.

Mary: "Who is that?" (motions to John's younger sibling)
John: "What are you talking about? I don't see anything."
Mary: "Oh John, I forgot you are still suffering from new sibling syndrome."

by yepyepyepyepyepyepyep February 2, 2014

bridge sibling

Your half sibling's, half sibling. When a child's parents seperate and go on to have other children, the relationship between those subsequent siblings. The original child acts as a 'bridge' between the two families.

This is Derek, my half-sister Mary's half brother. Mary and I share the same mother while Mary and Derek share the same father, he is my bridge sibling.

by GoJump April 25, 2016

three-quarter-sibling

Child of a person's father with that same person's maternal aunt or child of a person's mother with that same person's paternal uncle.

My three-quarter-sibling is a good person.

by Mr. Jacov November 23, 2019

National Bully your sibling day

National Bully your sibling (s) day is April 27th have fun with this.

April 27th is national bully your sibling day. You can bully your siblings on this date with no permission needed.

by KassWritesDefinitions February 26, 2023

Younger Sibling Privilege

A phenomenon in which parents allow their younger children to participate in certain activities that they did not allow their older children to participate in when they were that age.

This is an example of Younger Sibling Privilege: When Johnny turned 16, his parents told him he could not work toward earning a drivers license. When his younger brother, Timmy turned 16, his parents registered him for driving school.

by Stepman December 23, 2019

sibling from another dribbling

a friend or acquaintance that you are fictitiously related to; with different fathers.

similar to- sisters from another mister, and brother from another mother.

I swear you are my sibling from another dribbling!

by teebaba August 1, 2011

Sibling code of honor

An agreement between siblings to keep a secret from parents otherwise they might all get in trouble.

It's the sibling code of honor to not tell dad we were both at that party.

by Smiterm May 31, 2016