Sister, sister. - Jamie McCarthy/WireImage
But while each has released a number of albums, neither has really done anything musical-related in the past few years. (Ashlee is apparently working on a new album, though we'll believe it when we hear it.)
So while a collaboration between the sisters would have likely meant a duet five years ago, now it means... a tween fashion line.
Yes, Jessica and Ashlee are creating an apparel line for tweens as part of the Jessica Simpson Collection.
Women's Wear Daily says the items will be "geared toward the fashion-forward tween" and will include pieces of clothing modeled after Jessica's "girly, playful attitude."
"Creating a tween apparel collection was a natural extension for the brand," Jessica tells the magazine. "I'm excited to bring my sister, Ashlee, along as co-creative director of this division, because she brings a savvy rocker edge that defines today's tweens."
Ashlee definitely brings an "edge" that Jessica doesn't, though we're curious if today's tweens even know who Ashlee Simpson is.
- Ashlee Simpson