i think the problem with your reply is that it appeared you were saying that the child didn't need to face any consequences for her own actions, and everything is on mum's head. Maybe i read it wrong - but if i did, so did a lot of others from the replies in here
I didn't read it like that ... she did say

Say sorry to her and tell her that what MUMMY did was wrong and why. Then maybe talk about why we don't break things, and that we respect things.
I don't think that the post was saying that DD1 shouldn't take any responsibility, just that it shouldn't be used as an excuse for doing that.

I understood what the post was getting at and it didn't sound to me like there was any ill intention.

MissEm, it takes a while to find your feet. I think once you get used to it (and things being a bit harder to interpret from behind a computer screen), you'll come to see that BB is a great place to be. FWIW, I think your advice was quite good, but it is a bit of an art to learn to put it in a way that is not interpreted wrong from behind a computer screen. I think we all learn that lesson the hard way