LZ, still think you are right??? I can't agree more: 先撩者賤打死無怨~~係你無啦啦話人先~仲要話人無家教~!! That's her home and you was trying to impose your rule on her in her home, especially NOT trying to talk in a nice way.
Also, saying she is 無家教 even though you knew your mother-in-law could hear... who is really 無家教 now~?!
Your mother-in-law was nice enough to stop her daughter even though her daughter was accused as 無家教. Your mother-in-law gave you lots of "face". I don't think you appreciate it though. You even try to persuade your husband to yell back to his sister and expect your mother-in-law did the same. I guess you deserve a bad mother-in-law to yell at you all the time and then you will appreciate.