AITA for not letting my miracle baby niece be my flower girl at my wedding?

I am getting married in a month and I was thinking about having my 6 year old niece be the flower girl. But I was only thinking about it.<br><br>My sister had a very difficult time conceiving my niece and she is technically a "miracle baby". My sister is obsessed with her and doesn't let her out of her sight and she has a tendency to throw the "miracle" thing around. <br><br>I mentioned to my parents that I thought having my niece be the flower girl would be a really sweet gesture and they both immediately told me that I had to do it and that it would mean a lot to my sister. I said that while it would be a really sweet idea, I just mentioned it just as an idea, I didn't contact my sister about it. <br><br>Then I did end up deciding that I didn't want a flower girl at my wedding and decided to go for something a little more "unconventional" for my wedding and have a petal toss (where petal throwers throw the petals from the side of the aisle instead of a flower girl throwing them down the aisle).<br><br>I happen to have two cousins (one's daughter is 5 and the other's daughter is 6) who both have daughters around the same age and I thought this was a great opportunity to have them involve their kids and kind of go for a Disney bridal arch look with the petal throwers and have them in matching dresses at the sides of the aisle. <br><br>I asked them and they said yes and then I told my parents. They asked what I was going to tell my sister and I said I would just tell her that I decided against having a flower girl. They said that she'd be really disappointed and it would be great for her daughter to be involved in the wedding since she's the only niece and I should just let her be the flower girl anyway. I said no because I already asked my cousins and they could coordinate the dresses and I wanted them involved. <br><br>My parents said it wouldn't be fair to only involve certain family members and exclude others and that my sister would never ask me for anything. I said I wasn't excluding my sister but I already made a commitment to my cousins and it's only one flower girl (but multiple petal throwers) that I'm only not following through with because I came up with a different idea.<br><br>My mom gave me a whole speech about how my sister would be so touched that I gave her daughter this role and she'd never forget it. I said fine, I'll ask her. And then I sent her a text asking her if her daughter would like to be the flower girl. <br><br>She responded with "yes but I was really thinking she could carry a sign that says 'here comes the miracle that was born to a previously infertile mother and here comes another miracle that will be born to a previously infertile mother'". <br><br>I was supposed to answer her all day yesterday but I keep putting it off. She can't be serious, can she? I was already getting really sick of my parents bending over backwards to accommodate my sister just because of her hard time conceiving and this makes me feel like I'm being pushed even further into accommodating her weird obsession with her whole "miracle baby" thing. I just want to tell her no but I feel bad because I already said yes to her.