National Best Friends Siblings Day

Two siblings, a brother and a sister, smiling and hugging each other under a blooming tree, surrounded by colorful balloons..
National best friends siblings day illustration

Welcome to National Best Friends Siblings Day, where we celebrate the unique bond between siblings who are also the best of friends. Whether you're sharing secrets, borrowing clothes (without permission), or just annoying each other, this day is all about appreciating the special relationship that can only exist between siblings who happen to be best friends. So let's dive into the internet history of this delightful day!

When is Best Friends Siblings Day?

It's national best friends siblings day on the 9th June.

The Internet History of National Best Friends Siblings Day

On this day, we commemorate the countless pairs of siblings who not only share family ties but also share a fantastic friendship. It's a day to honor the brothers and sisters who have been each other's partners in crime, shoulder to cry on, and biggest supporters in life (even if they do squabble over the last slice of pizza).

The origins of National Best Friends Siblings Day can be traced back to the depths of online communities and social media platforms. It was on June 9, 2015, when the internet exploded with 48 mentions of this joyous day. People from all corners of the digital world began posting heartwarming stories, adorable photos, and hilarious anecdotes celebrating their incredible brother-sister friendships.

The hashtag #BestFriendsSiblingsDay quickly gained popularity, making its way across platforms like Twitter, Instagram, and Facebook. The internet was abuzz with heartwarming tales of sibling love, with people from all walks of life sharing their appreciation for their brothers and sisters who are also their best pals.

This heartwarming celebration not only brought families closer but also became a global phenomenon. From heartwarming posts shared by celebrity siblings to everyday people expressing their gratitude, National Best Friends Siblings Day has become a day to take a moment and acknowledge the amazing friendships that can flourish between siblings.

Fun Fact:

Did you know that research suggests sibling relationships can positively impact psychological well-being? Studies have shown that having a close sibling relationship can lead to increased happiness, reduced feelings of loneliness, and enhanced social skills. So next time your brother or sister steals your favorite shirt, just remember, they're actually doing you a favor!

History behind the term 'Best Friends Siblings'


The Rise of the Term 'Best Friends'

In the 1940s, the term 'best friends' gained popularity in English-speaking countries. The idea of having a 'best friend' referred to an individual with whom one shares a close bond and engages in various activities, confides in, and trusts above others. This concept resonated deeply with people longing for a special connection with someone, akin to a sibling-like relationship.

Late 20th Century

Intertwining Best Friends and Siblings

As the notion of 'best friends' continued to evolve, people began recognizing the similarities between these strong friendships and sibling relationships. This realization led to the coining of the term 'best friends siblings.' It describes the unique bond between individuals who are best friends and feel like extended family, often sharing even closer ties than biological siblings.


Popularity in Contemporary Culture

In the 2000s, the term 'best friends siblings' gained popularity and recognition in contemporary culture. It became increasingly common to find stories in books, movies, and television shows that explored the special and often unbreakable bond between individuals who consider themselves best friends siblings. This concept resonated with many, highlighting the importance of chosen family and the enduring nature of certain friendships.

Present Day

Embracing the Best Friends Siblings Phenomenon

Today, the term 'best friends siblings' continues to be used as a way to capture the profound connection and love between individuals who are more than just best friends. It represents the fusion of kinship and friendship, emphasizing the integral role these relationships play in our lives. Whether it be through popular culture or personal experiences, 'best friends siblings' has become a recognizable term that celebrates the strength of such relationships.

Did you know?

Did you know that research suggests sibling relationships can positively impact psychological well-being?


fun loved ones

First identified

8th June 2015

Most mentioned on

9th June 2015

Total mentions


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