beta
Why did the sister suddenly show up? She had no reason to check in.
Meirin hadn't gone outside and no news of how well she was being treated had spread, so the sister should have been at home, laughing at how miserable her sister probably was.
If they want to use this trope, at least make it believable and put some effort into it.
I'll let this marinate and then come back to see if the writing has improved later.