Ah... now the word sorority makes sense!
so does fraternity
Nice! This will definitely help me to remember this one
Atunci ea este mătușa mea!
What is wrong with 'her and my mum are sisters'
Unfortunately it is not grammatically correct, nor the literal translation. And duolingo insists on the first point
Why is "my mom" wrong ._.
It's still an enigma to me, how soră becomes surori in plural
There is a 'suroră' variation of the singular, which is possibly older.
I typed sorori" and didn't get a typo flag. If I hadn't looked at the comments I wouldn't have realized it was wrong.