Have you ever found out someone close to you self harms?

i self harm but i found my little sister doing it and it kills me to see her like this because i know what it is like and i don't want her to turn out they i have and i am trying to help her we are both getting help now but it is sad to see how it affects you when someone you love is doing it but i used to think when i did it no one cared but i am trying to help my little sister.