It's not about the dress. It's about control. The threat to unalive the unborn baby was an attempt to force OP's hand. "My sister will unalive her unborn child if I don't hand over my wedding dress, so now I have no choice but to give it to her." I'm trying to figure out why OP is still talking to these people. I hope she goes no contact with them and doesn't invite them to her wedding.
Bruh the nerve of that sister... "you don't know what it's like to be a good parent because you're child free" She doesn't know what its like to be a good parent because she's not even giving her baby a chance at life, OVER A DRESS! If this woman is really gonna put the value of a dress over her own damn child, she does not deserve to be a parent in the first place.
If she goes through with the deletion he will share all the texts as proof, and file and fight for full custody of said baby... I'm not an expert but I do know you can't get custody of a baby that has been deleted causing you to seek full custody... The math just ain't mathing here. Lol fake stories are fine but make it make sense at least!
I also would keep my dress in a place she can't access if you decide not to wear it. Who knows? You might decide to have a celebration of your marriage later and want to wear it. It was pretty presumptuous of the two of them to unilaterally decide she should wear YOUR dress that you designed and paid for before you do. She's definitely a user and guess who raised her that way!
You know, if she's so easily willing to end a pregnancy she apparently want over a dress maybe she doesn't really want the kid and the kid too honestly would be better off aborted than with her. If she was my sister and she kept the pregnancy going even if denied the dress I wouldn't hesitate to tell the kid once older how their mom almost aborted them over a dress. If she can do that to her unborn kid who knows what else she can do.
Sorry but your wedding dress is your personal belonging and surely worth a few thousand dollars. This dress is unique and you deserve to be the only one ever wearing it, or maybe giving it to your children if you ever decide to have any. She just was envious about you having a unique dress that you designed yourself and not having to buy sth from the store like she peobably must. I'd have offered her to design her a dress, too but I'd not have offered my dress to her. You never know in which state it comes back and your memory will always be divided by her and your wedding if you look at the dress. Don't do it, she just can't accept a no and tries to do everything she can to get a yes instead
Content creators call death or violence of any kind something else, because platforms demonetize their content if it actually acknowledges that the real world is full of violence, parents might complain that the children they're letting the Internet raise are being exposed to the real world too young. Like school shooter drills don't already do that, or something
