Yeah, my sister is 26 and I'm 20. Basically my chores are just to take out the trash + recycling on Tuesday/Friday, do my own dishes, put stuff in the dishwasher and cleaning up after myself. Really nothing big at all. My sister has a job and I don't (I'm also not in school yet) and my sister doesn't have a ton of chores either but way more responsibilities and she's also the one who wanted two dogs so whenever they do something wrong (which is a lot,) she gets blamed because she's not looking after them. She works a ton so I watch them a lot but I still feed them and do everything I'm told. She just decides one week that she wants to do her chores and the next that she doesn't, and both mom and I noticed it and my mom has pretty much been fed up with it for months. Like my sister, for some reason, really doesn't learn. But luckily her problem has nothing to do with me.
We've only been in this house for maybe 7 months now. Not sure how old the dishwasher is, I don't know if they got a new one before we moved in or what.
Seems to me like your Mom needs to just throw her out on the street.