Quoting ♥ darah ♥:" <blockquote><b>Quoting MyPurrrtyBabies:</b>" Tough, tough. Its OP's DD room and if ... [snip!] ... doesn't want to be around a bossy-impatient 12 yr old, lol"</blockquote> Its not always black and white like that."
Well, if she doesn't want her stuff messed with she should keep it put up...there is no grey area for that, that is just common sense. I feel bad for OP's sil bc she probally is going through a hard time being with out her Mother, living in a unfamilar house and location BUT she knows a 2 yr lives in the house and gets into everything, OP's sil had cabinets to put her stuff away in yet she doesn't.
Maybe OP and her SIL can come into a agreement/arrangement or understandment on what they can do. Putting a 2 yr old in time out only goes so far, she( the sil ) is gonna have to put her stuff up.