Real Life Problems

Alright, so i have 2 older siblings and a younger one. My eldest sister is the problem. Shes had a habit of stealing money and shit arount the house, and this is an open secret among our family. My mom told us that when we were kids a 500 note was missing from her bag and she asked my second sibling about it ( this was at night and every one else was asleep, we siblings all share a room btw) second sibling said they hadnt seen it and mother left the room, so they lay down to sleep....around 10 mins later they see eldest sis sit up and pull out the note from the gap above her in the bunk bed, open the note, stare at it, and then she puts it back and goes to sleep.
So anyways the other day second sibling asked me to buy them tickets to a movie and i brought back her money with two 100 notes and told her i couldn't keep the cash with me cuz all my cash has been going missing from my wallet the past year or so. The next night i remember clearly leaving some cash in my wallet (around 5 diff types of notes added upto almost 50 in total, btw i had cash on me that night cuz the cinema only accepts cash fsr, there's some shady shit going on there) next morning i go to work and all my cash is GONE (╬￣皿￣). I was so pissed i ranted in the fam grp chat about it losing my cash in our shared room, and asked for it to be returned if found. Not even a minute later second sibling calls me and tells me that one of the 100 notes i gave them was missing from their pouch, how shocking!! I actually didnt think she would steal money from second sibling cuz thats the sibling shes on best terms with.
Now you may be wondering how i know shes been stealing my shit. So my mom bought me pair of very expensive good quality sunglasses, which i let my family borrow if they're going on a trip or if i dont use it. One day i left it on the table while running some errands (shopping etc...) and when i went to step out again, it was gone. The only ones in the house were me, my dad, and my eldest sis. My dad was deeply sleeping on the sofa (i had tried to wake him for breakfast but he was put cold) so i knew it wasnt him, and eldest sis had stepped out 5 secs ago, i called out the door to her and asked if she'd seen them but she said hadnt.
Fast forward 3 days, im still looking for them, checked the whole house, asked my family, and the only conclusion was that she took it, so when she was home and i had the room to myself i locked the door and went snooping through her bag. What i found was an unopened pregnancy test, cigs and voila, my beloved sunglasses sitting at the bottom of her bag. Glasses that she denied having seen when i has messaged her the day before. I took a photo of it sitting there in her bag and decided to confront her later that night infront of the rest of my siblings....
Unfortunately, that night i saw the glasses sitting in plain sight on her shelf and she told me that my baby cousin must have put it there, thay pos
Anyways, i told my mom and as always she told me i should leave my things around her, which is impossible to do in a 2 bedroom apartment with 6 people living in it.
Thanks for listening to my rant guys ヾ(╹◡╹)ﾉ~

So I'm just curious to why people are supporting this absolute monster my mother went through postpartum depression while my dad was abusing her how come she didn't kill me I just think it's sick that people are defending her my opinion ┑(￣Д ￣)┍