Sienna Miller to launch clothing line with her sister

If there's one thing that Sienna Miller is known for - besides her relationship with Jude Law and her antagonistic relationship with the city of Pittsburgh - it's her fashion sense. Now Sienna plans to make use of her coveted style and is designing a line of clothing with her sister, reports Women's Wear Daily.

Sienna and her sister, Savannah - who is already a designer - will launch a collection of 80 pieces called Twenty8Twelve by s.miller in fall 2007. The name of the line comes from Sienna's birthday, the 28th of December. Items in the first collection will include denim, knitwear, tailored jackets, dresses and outerwear says WWD. Savannah said, "People wanted us to put the line in our names, but we wanted it to be more abstract."

Sienna explained her reasoning behind going into the fashion business. She said, "I've always loved fashion, and Savannah got a First in design at Saint Martins. We hadn't thought to pursue it together, but this just happened organically. And setting up a label with your sister is a lot of fun - there haven't been any fights yet…Because of my job, people are willing to invest in the business, but my sister's an incredible designer, and it's a great opportunity for me to work with her."

Sienna is currently the face of another line of clothing: Pepe Jeans. Pepe's owner, Carlos Ortega is also acting as a backer for Twenty8Twelve.