Oh that's not true Petal. I've spoken at length with your ex sister-in-law and seen the photos, I've gotta agree, that back bedroom is a right ol' mess and that's saying nothing about the laundry and bathroom arrangement. That clothes pile waiting to be ironed has been stashed there in the corner for over 3 months now.
Now go and give that kitchen, and especially that oven, a jolly good scrub down. Come and report back when it's complete, and the ex SIL and myself will come and inspect it to make sure it's done.
Sh*t Mary Sue, you have met her!!