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NYC Fashion week starts today, and some of Hollywood’s most notable fashionistas won’t just be watching the shows, they’ll be modeling in them too — and it’s all for a good cause. Celebs like Heidi Klum plan to help out The Heart Truth, a charity that increases awareness about women’s heart disease, by strutting the catwalk during the Diet Coke-sponsored Red Dress Collection runway show at Bryant Park. The annual charity runway show features one-of-a-kind dresses created by more than 20 of America’s top designers and modeled by some of your favorite stars, including Klum, Jenna Fischer, Emma Roberts and Leighton Meester. And if you can’t get to the show, you can always buy the Be True to Your Heart lip palette, $40, created by Red Dress donor Bobbi Brown. Click here to watch highlights from the runway show!