If you still like your best friend then try to get her back or let her go with your sister if that's what your friend wants. Or mabey your friend could be friends with your sister and best friends with you.
The best sister is the world would have to be Miss Poppy Smithers.She is always there for me and is my best friend. To truly find the best sister you have to ask your self would you call your sister your best friend? I would and that is therefore why Poppy Smithersis the best sister in the world to date.
Immature
her sister
Yes. I would know from experience. It may be frustrating sometimes when you want to hang out with them and so does your sister, but then you can all hang out together. You can just both have the same friend.
Molly was a sister to her well like a best friend to her.
Your crazy...and he's your BEST friend! Hell no.
ignore .
her sister Haylie
You let your best friend and her sister work it out. Don't get in the middle of that - that way lies disaster.
She was only her best friend but not her half sister. Simone lie about it.
She probably just wants to feel more mature. Ask your sister to give your friend the brush-off in the nicest possible way.