Apologies in advance for a long and resembling post about something probably very silly...
Me and my family (dh, 3 year old dd and 1.5 year old twins) have temporarily relocated to Asia for a year due to my husband's work. In our home country I'm working full-time, but here I'm at home with the kids and doing all the cleaning, cooking etc. We don't have any family and hardly any friends here, so to get some much-needed help, mainly with the kids, my husband's unemployed sister has come to visit for 6 months.
I'm an introvert with a high need for boundaries, and I like things to be done my way (especially here; I find taking care of three small kids alone doesn't work without strict routines and order).
My sil is a dominant person who also likes things done her way. She's good with the kids, and she does help (despite constant conflicts because of differing views on parenting). However... Most of my house-related routines are not to her tastes, and as she doesn't like the way I wash dishes, clean or do laundry (her words), she has now taken over those chores. Which could have been nice, if it wasn't for the fact that while doing this, she also keeps re-organizing everything she comes in contact with. Changing the order of the kitchen cupboards, relocating the play area from dd's bedroom to the living room (without asking me first) and re-organizing my husband's desk (and misplacing important papers while doing it) are just some examples.
At 3am this morning (SIL for some reason tends to be awake during the night and awake during the day), while getting some water, I saw that she had taken out all the clothes of the kids closet, folded them and was starting to put them back in different places than they were in before. When she saw that I moved some of them back to their original places, she got upset ("are you kidding me?? I'm organizing and you mess it up??"). My husband thinks I shouldn't make a big deal of any of it and just let her get on with it without making a fuss, as none of it is very important.
Am I being unreasonable in thinking her actions are slightly disrespectful? Should I really just let this go, or is it actually reasonable to demand that she asks me before she starts to change things?