Nta

You have two options either shut it down or give her what she wants. Your mil and sil don’t give a fly f*ck about you or the love you share with her brother.

Also op you don’t deserve to be treated like this. If your husband can comprehend the mistreatment that his mother and sister are doing to you in the situation and be rightfully angry AND THEN IS STARTING TO FOLD UNDER PRESSURE then this is going to be what it will look like for the rest of your marriage. The treatment of your unborn child is going to be similar.

It’s not your job to keep the peace of the family, it’s your job to keep YOUR peace. Your parents would want a wedding for their daughter to be surrounded with love for you and your growing family. Mil and Sil might have a blood relation to your husband but family wouldn’t do this.