If you've just come out of rehab for an "eating disorder" and you are making your first public appearance, perhaps it's not wise to a) look as if you are being held up by the comparative heft of your twin, and b) wear a shapeless sack made out of the tablecloth you stole from rehab so that you'd Always Remember. [Nice of Ashley to generously show solidarity by wearing a shapeless shift of her own.]
The rumor is that Mary-Kate came out of rehab ten pounds heavier. This dress choice makes it look like she lost weight. I really hope she just has no sense of style, and not that she's dressing this way because she's hiding her newfound obesity. Poor kid. CINCH IT, Olsen twin -- you have nothing to hide. Also, keep eating meatball subs. You won't be sorry.
they look like they're wearing the prom dresses from 'the virgin suicides.' except looser.