The black sheep

If they’ll only be participating in the reception, I wouldn’t worry about their attire.

She’s standing at your husbands side right? If so then I do think it’s ok if she looks slightly diff from your bridesmaids

There’s not much you can do, I’d just let it go. It won’t matter nearly as much to your guests as it does to you. At a friend’s wedding last year one of the groomsmen decided to wear a navy suit he had rather than pay to rent the black suit everyone was supposed to be wearing. We all noticed he didn’t match, but beyond that it didn’t matter. They only printed pictures of the wedding party in black and white so it wasn’t as noticeable. It happens, don’t overly stress about it! Try to relax and enjoy the last week of your engagement!

View Quoted Comment There’s two grooms maids, one has a long dress like my girls and one has a short dress unlike everyone else

Did he communicate to her that it needed to be floor length, and she decided to get knee length regardless? Or did she not know? If she KNEW and went ahead anyway, you have every right to be upset and ask her to get a new dress. Did you say for them to purchase a regular dress on their own like from a dept store? If so, she could easily exchange it. He should let her know a floor length was asked, and she will stand out otherwise. I get the annoyance, but this close out, there may be nothing you can do. She won’t be in every picture, and like pp said, no one will really care who attends.

Annoyance of your request being ignored aside, as another poster said, this is something that your guests won't pick up on as much as you do. I say don't stress about this because it's a bit too late to fix it anyway. Take a bit of solace in the fact that she will feel pretty and confident in what she chose to wear and put your attention to other things as you are in your final days of prep.