Visiting dog pooped in my sons room. No one mentioned it...

[Toooldfornonsense]

More of a WWYD but let’s see how this pans out...

Myself and my husband work long hours and do crossover shifts which means we don’t need to pay childcare. This includes one day a week where parents come and pick up our children from school.
My parents are more than we deserve and offered to look after our children for a week whilst myself and my husband went on holiday for a week by ourselves ( it’s very rare we use our work holiday together and I’m under no illusion - we are extremely lucky to a) have parents that can and will offer to do this and b) be able to afford said holiday).
A couple of days before the holiday my mother asked if I’d heard from my sister about her and my young nephew staying whilst we were away. I said I hadn’t and that
it wouldn’t be a problem but it was a problem that she hadn’t mentioned herself. Not long after the call she text to ask... said it was ok. No problem. She said she’d stay in my youngest child’s bedroom with my nephew and my youngest child would sleep I bunk beds with my oldest.
Fast forward to return from holiday and I walked into my oldest sons room which stinks of what can only be described as sick. Waited until my son came home from school and asked if anyone had been sick in his room. He looked very uncomfortable at the question (he is only 8) and after a few questions admitted that my sisters dog had had diarrhoea on his bedroom floor in the night two days before we got back. Apparently there were multiple clean up attempts but the carpet is ruined and the rooms still stinks after multiple attempts by myself to clean it.
The problem I have is that no one has said anything about it (don’t blame my parents, they do a lot for us and it’s not their place. It’s not their dog). My sister on the other hand, left the morning her dog made and mess and had not text to say about the accident or say sorry since. She hadn’t even said thanks for staying at our house (which she wouldn’t have told us hadn’t parents not said. Nor has she mentioned the mess her dog made). I’m so mad about this. What is the best way to approach it?

There’s dishonest and downright evasive behaviour here.
Not properly asking you whether she could stay, then damaging property and not bothering to tell you. It’s a basic lack of respect.

She came to stay in your house while you were away, & didn't ask or tell you, slept in your bed, & allowed her dog to crap on the carpet, then left without cleaning thoroughly.
I would tell her she needs to pay for professional carpet cleaning. & if that fails she will be required to replace the carpet. She has behaved in a deliberate dodgy manner, & whilst it was an unfortunate accident, the behavior leading up to it & following it leaving your parents keeping her secret, & you with an unusable bedroom without an apology, is unacceptable.

If your cleaning efforts have failed, it’s probably in the pad underneath.

I don’t think it’s unreasonable for her to pay to replace the carpet. i might Offer to split the cost since you aren’t replacing something brand new.

Carpet that has to be replaced due to accidental damage is an insurance job. Could you claim? If so, claim on the insurance, get new carpet, make very breezy conversation about why you are having to do it like it's no big deal. You come out smelling of roses and she feels guilty but your holiday is not awkward because you hold the magnificent high ground.

@Purpleartichoke - the OP wouldn't need to be considering replacing it at all if her Dsis dog hadn't shat all over the carpet. Sister pays for the entire costs associated with cleaning and/or replacing the carpet.

She’s completely disrespected you, your family and your home.

I would not hesitate in phoning her and asking for an explanation and her plan for replacement of the carpet (I’d give her 28 days).

I wouldn’t bother keeping up the pretence of a good relationship for the sake of the children, as a PP said it’s only teaching your children that you are happy to be treated (quite literally) like shit!

She’s a solid gold CF!!!

Yuck it will have seeped through to the underlay. The whole lot will need to be ripped up and replaced. I’d ask her to pay my insurance excess as it needs replacing. Or just give you cash.