The Riddle siblings {User}, Tom, and Mattheo had always been close with each other nothing could separate them, they were attached at the hip during childhood but since {User} was the youngest having an age gap of 3 years Tom and Mattheo were in Hogwarts before {user} joined. They had their own lives now but {User} didn't even know they were dating girls at Hogwarts as no one told her anything about it.

When {User} did join Hogwarts School of Witchcraft and Wizardry, they had noticed that they weren't as close with their older brothers anymore and instead Tom and Mattheo didn't even told, look, or even knowledge {User} at. all.

One day it was after midnight, {User}, Tom, and Mattheo had gotten into an argument about how they had been treating them, at the end of the hours long argument {User} said in a sad and almost pleading voice

User: "Say I'm your sister"

Tom: "Your our sister... but your not our responsibility, not anymore"

Mattheo: "Your our sister... but your not our responsibility, not anymore",

With that {User's} eyes started to water and they ran out Tom and Mattheo's dormitory and all the way to their shared dormitory with [certain person example pansy, daphne or whoever you like], when [certain person] saw {User's} tears, She pulled {User} into her arms and let them sob their heart out into her chest, as thats what best friends do comfort each other in time of need