Hailey doesn鈥檛 play by anyone鈥檚 fashion rules. She鈥檚 a risk-taker through and through, donning shower curtain-like pieces and naked getups with regularity without a care in the world.

Which is why it makes total sense that for her stint as her sister, Alaia Baldwin鈥檚, Maid of Honor this weekend, she did the same, slaying her duties in a totally chic, black formal gown and a matching lace choker, Mary-Kate and Ashley Olsen style.

View this post on Instagram

maid of honor and the Bride's mom 馃槏

A post shared by Ireland Basinger-Baldwin (@irelandbasingerbaldwin) on

While it was quite a different look than say, Taylor Swift鈥檚, who also served as a 鈥榤aid this weekend, it was certainly no less gorgeous: The famous little sis kept it sleek and slinky with the dress鈥檚 fitted silhouette and plunging V-neckline, setting her apart from her cousin Ireland Basinger-Baldwin, who wore a similarly stunning black frock with a boat neckline.

If Alaia鈥檚 Instagram story was any indicator, she was the perfect gal for the job, fixing the bride鈥檚 own gorgeous choker no less than 鈥3,000 times鈥 and whooping it up with her on the dance floor.

After the big event, the 20-year-old appeared to be having a blast, also showing her mom a thing or two about breaking it down. 鈥淛ust harassing my mom,鈥 she captioned an adorable video of herself shimmying around to Drake鈥檚 鈥淚ce Melts.鈥

View this post on Instagram

Just harassing my Mom

A post shared by Hailey Baldwin (@haileybaldwin) on

The runway stunner also gave us a closer look at her hair and makeup, posting a pensive selfie of herself enjoying a lime-filled beverage. Keeping her blonde locks pulled away from her face and most of her makeup muted with nude lips and a neutral face palette, the focus remained on her groovy heavily winged liner (and those gorgeous white cross earrings).

View this post on Instagram


A post shared by Hailey Baldwin (@haileybaldwin) on

Needless to say, girl looked every bit as elegant and gorgeous as any bride could ever hope for, all without a stitch of color.

Lookin鈥 good, Hailey!

What do you think of black for a maid of honor dress? Tell us over @BritandCo.

(Photo via Alberto E. Rodriguez/Getty)