I am hoping for some advice on something I am having a REALLY hard time with. Its kind of a long post and I am sorry.
Little back story so that its clear whats going on. So, my fiancé and I picked out our wedding party in September 2018 when we got engaged; we had a plan to get married in July 2019 but after being told I would never have kids, we found out we were pregnant December 2018. Super exciting, we had our daughter in August 2019 therefore, we pushed our wedding to this October 2020.
My fiancé has all 3 of my brothers standing up as groomsmen, so we asked 1 of them to have his kids in the wedding as well (realizing now, HUGE mistake). We made some changes to our people & made them a JR Groomsman, a JR bridesmaid & a female ring bearer. My SIL has been SO overbearing with all of the wedding planning already. She is not in the wedding (we are not and have never been close whatsoever). She doesn't like the color of the dresses for her daughters, she told me SPECIFICALLY how she wants her kids hair done, the flowers she wants in their hair, the fact that she needs to be involved in all of the wedding events (WHICH IS NOT HAPPENING) and now, she is trying to tell me that they will be wearing high heels and not the cowboy boots in the wedding.....all of this she said in the group chat with the whole wedding party (how embarrassing !!!). All of my friends in the wedding created a separate group chat without her and every single person has told me how uncomfortable she has made them feel due to her arguing with me . We decided that it is better off to ease tensions and take the elephant out of the room by removing the kids from the wedding....HOW DO I NICELY TELL HER WE ARE TAKING THEM OUT WITHOUT HER FREAKING ON ME!!!! HELPPPP! I am desperate.