Rant about Babysitting

I watch my niece almost everyday because my sister works as a supervisor so she is busy. I love my niece with all my heart but I’m constantly told I will be paid or have a day off or many other things and it never happens so I’m watching her in pain (I have fibromyalgia and don’t have the money to get my medicine) and on top of that I’m told all I do is sit on my ass and do nothing when I’m watching a 1 almost 2 year old baby running around and if the kitchen isn’t fully cleaned they act like I have done nothing and if the bathroom is a mess it’s the end of the world. This baby girl isn’t a cranky baby but is hyper and always on the move getting into something and if I am having a bad fibromyalgia day it takes a lot out of me. I’m just so upset and angry at them for saying I do nothing when I clean, cook, grocery shop, give the baby baths, change her dirty diapers, run errands, etc. on top of that I usually don’t get to sleep until midnight because they are loud and I am awake half way through the night to rock my niece back to sleep and am back up at 5 or 6 in the morning

I’ve literally have screamed at my sister for saying she can’t rely on me when I am the only person who has stepped in to take care of her child.

Honestly the only person I care about is that baby girl and her huge heart and smile.