So I just got engaged at the end of April. While talking to my sis I mentioned my BFF being my maid of honor. Now my sis is pissed & in her feelings. My sister & I have never been real close but we're working on it. My BFF & I are closer than sisters & I know she'll take on the role & get everything done. But how do I relieve the tension between them? They don't like each other now.