Kristin & Heather: 2 Girls, 1 Dress

6/10/2009 2:13 PM PDT BY TMZ STAFF
Here's 22-year-old reality TV star Kristin Cavallari wearing a cutout Herve Leger dress in L.A. on Tuesday (left) -- and 39-year-old "The Hangover" star Heather Graham in the same little black number in Ireland on Monday (right).

Kristin Calvallari and Heather Graham
Both went commando.