'My house, my rules' only works so far, though. It's fine when it's about allowing them to eat in the sitting room, or watch TV at lunchtime, but when it comes to matters of principle, I can't agree that it's a good idea.
I didn't want my children to be defined in terms of their behaviour, so I would say 'that was a naughty thing to do', or 'do you think it would be kinder to your sister to let her share?' or whatever. I didn't want them to be told 'you are a naughty girl/boy', or 'you are unkind/selfish', which is how my mother was used to speaking to children.
I had to be very firm about it, and I know she was rolling her eyes at what she saw as my being unreasonable/indulgent, but it mattered to me because of how I was brought up.
I wonder if there is a similar issue going on here? Without asking the daughter, though, the OP will never know what she 'did wrong'.
