Taeyon, Jessica and Tiffany were best friends since the the accident:

     ======================  Flashback  ===================

One day Jessica and Tiffany's mothers were best freinds when they were at the University... SO Jessica and Tiffany became best friends. One day Tiffany and

Sica went to the park roller skating, they both did their first try to roller skate : Tiffany bumped into a tree, Jessica bumped into a girl that was Taeyeon, they 

were both the same age and Sica asked forgiveness for bumping into her, and asked her " Hi, I'm Jessica, what's your name?"

" Hello, I am Taeyeon" Taeyon replied... " Do you want to be friends?" Jessica asked her. Taeyon said " Sure" Then Sica said " I want you to meet my BFF

Tiffany, she is over there she bumped into a tree"...  Jessica and Taeyon giggled. And the three girls became BFF's

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