Start piling her shit in sister's room.

mrsconn23

Dear Prudence,

My house only has three bedrooms. One is my office. I work remotely. My sister just got out of an abusive relationship and moved in with me. She shares the guest room with her 12-year-old daughter while her 20-year-old daughter sleeps in the upstairs den where my office is. I have never seen a more slovenly or selfish person in my life. My niece doesn’t work or go to school. The den is a disaster—clothes everywhere, trash left on the floor, dirty dishes left behind. Getting my niece to clean up her act is like pulling teeth. She will “get around” to it. Every day I go up the stairs to start my work day, it is a constant fight. My niece refuses to listen, will curse at me under her breath, and go lock herself in her mother’s room. My sister throws her hands up in the air and says she can’t force her daughter to do anything and it isn’t like we can throw her out on the streets. I am this close to doing just that. I don’t want to but there is no earthly reason why a grown adult can’t clean up their messes or contribute to the household.

—Last Straw

flantastic

Sounds like there need to be three in the guest room.

banana468

"Let's be clear.  There are rules to living here that must be followed and not following them voids your ability to live here." 

climbingsingle

Yeah, I'd ban her from using the den. 

banana468

climbingsingle said:

Yeah, I'd ban her from using the den. 

And also, the sister is either the point person or isn't.  So you can tell the sister that if the behavior continues it's the 20 yo that will be unwelcome at minimum. 

short+sassy

mrsconn23 said:

Dear Prudence,

My house only has three bedrooms. One is my office. I work remotely. My sister just got out of an abusive relationship and moved in with me. She shares the guest room with her 12-year-old daughter while her 20-year-old daughter sleeps in the upstairs den where my office is. I have never seen a more slovenly or selfish person in my life. My niece doesn’t work or go to school. The den is a disaster—clothes everywhere, trash left on the floor, dirty dishes left behind. Getting my niece to clean up her act is like pulling teeth. She will “get around” to it. Every day I go up the stairs to start my work day, it is a constant fight. My niece refuses to listen, will curse at me under her breath, and go lock herself in her mother’s room. My sister throws her hands up in the air and says she can’t force her daughter to do anything and it isn’t like we can throw her out on the streets. I am this close to doing just that. I don’t want to but there is no earthly reason why a grown adult can’t clean up their messes or contribute to the household.

—Last Straw

Oh yeah?  Hold my beer.

The sister and especially the older daughter are walking all over the LW because there haven't been any consequences.  And they don't think there will be any consequences.  Disavow them of that notion.

The LW needs to decide what they expect from the sister and her children.  And what they'll do if the family doesn't comply.  What they ACTUALLY have the backbone to do.  Because if they set a line and then the family breaks it, the situation will get worse.

First off, the daughter can't sleep in the office anymore.  I wouldn't even give a chance to correct that because many chances have already been given.

Does the sister work?  If she does, she needs to start financially contributing.  If she doesn't or the LW would rather the sister save the money, then the sister needs to take on the bulk of the household chores.  The younger daughter should also be helping for what is an appropriate amount of time/chores for a 12-year-old.  Obviously the older daughter should also but since she won't, her work share becomes the sister's responsibility.

MesmrEwe

"This is your notice, you are 20yo, come September, you're going to experience life more than 10 miles from here.  You are old enough to choose your path, you can go to live-in college/technical school, you can choose a branch of the military, you can choose the path you take, but you will not be living here to do so.  This may until your Mom gets back on her feet with an apartment of her own, a place to visit over breaks, but the time has come that you learn to adult."

Backbone and boundaries time!!!  There needs to be clear parameters to get the sister out of the same house and into their own starter apartment, even if it's a one-bedroom...  

CharmedPam

Sister and niece don’t seem very grateful.
lock the den door and throw an airbed in the guestroom. Here’s your new bed, niece.  It may speed up the “get the heck outta here” pace too