>>3411730Be glad that you got your lesson very cheap. And i'm serious about it, you didn't zip your bag and you didn't tell your sister (and everyone else in the room) that there is some equipment in the bag, that can fall down. But now you have most precious things in the world: knowledge and experience. So you'll be careful next time and wont lose more expensive glass because of same mistake.
And don't forget to tell her that it's not a big deal. Or just lie that lens is fine. No matter how much you love photography, it was just a thing.