I don't know if you can hear this but it's worth a try.
I'm so sorry I couldn't be a better big sister. I'm sorry I couldn't save you. I know it's not entirely my fault but I miss you and I still feel bad to this day. I'm so sorry I couldn't protect you how I wanted to.
I'm so sorry.... Ooooohhh I'm sorry. I miss you, my angel. You mean the world and more. I promise I will get better and live a happy life.... For both of us because you deserve that. It's definitely gonna take time but once I make a promise especially to my sweet sisters I keep that promise. Ooooohhh I'm soooorrryyy!!! I miss you every day. I'm sorry. You deserve everything good and more. Sometimes I will cry for you. My heart aches. Oh I'm so sorry for everything. I love you my sweet sister. The dirt bags who did this will definitely get punished sooner or later so we will all have justice. I love you....