Check out those sleeves!

Ashley Olsen at the 2019 CFDA Fashion Awards
Credit: James Devaney/GC Images

Getting ready for a friend's wedding isn't exactly easy. There's travel to book, a card to purchase (not to mention a check to write), and, of course, you must pick out what to wear to the main event. Ashley Olsen, however, is a fashion designer. When it came time to get ready for Jennifer Lawrence's big day, she likely had a look in mind already: a pleated black dress from Marc Jacobs's Fall 2019 collection.

While it's a bit surprising that Olsen wouldn't choose something from The Row, her line with sister Mary-Kate, we can see why she was drawn to this particular piece. The poofy, balloon-sleeved cape and all those sequins are attention-grabbing, but at the same time, are balanced by the dress's dark color. Plus, considering the wedding was attended by a bunch of celebrities and J.Law's Dior gown had it's own hotel room, there was never a risk of being too over-the-top and upstaging the bride. This was hands-down the perfect choice.

Ashley Olsen
Credit: Backgrid

The paparazzi was only able to get a quick shot of Olsen wearing the design, but since it once appeared on the runway, we've got a photo of the front, too. It's a true party-meets-princess dress, and we love how the star went with casual, beachy waves, pulling her hair back into a big clip.

Marc Jacobs Dress Fall 2019
Credit: Slaven Vlasic/Getty Images

Should you want to snag Olsen's dress for yourself, it's currently retailing at $10,000 on (unfortunately, those sleeves aren't included). But if you're not willing to spend that much on your own wedding guest look, we also have plenty of outfit ideas, which you can create using what's already in your closet.