I don’t really know what happened to her

I have a big sister, Niela, she was the purest soul I have ever seen, she loved makeup and punk fashion, she was called Don by her friends because of her masculine style of dress, she was very talkative, very cool, she was the kind of person i want to date, yet a few days before christmas 2013, she committed suicide in her room while my mum was getting me ready for school, that day was a thursday , she came up after her breakfast in an effort to get herself ready to go to high school, she never came down… My mom walked me to school, she talked with a friend at she then she came home, she saw that my big sister’s shoes were still there, she entered her room and saw my dead sister, Niela left two notes:
one for me
one for my mom
She saw (my mom) that the box my sister put a lot of memories in since she was nine was open, she looked inside and saw a polaroid of my sister sitting on her bed and smiling with the caption “after all, I’m the only thing I need to remember” written on it, Niela also put her diary there.
We still don’t know why she did this, and now that I’m older, I want to read the note she left for me, but I don’t know how to ask my mom to do it…
R.I.P Niela, you left us but not our heart, good sleep my darling <3