Make sure you check out the Winter edition of this year's One Praise Magazine. In the magazine is a feature article on Katie & Karleigh and how they live their daily lives.

Here's a snippet from the article:
Katie (17) and Karleigh (15) along with the support and help from their parents, run a Jonas Brothers fan site, jonasbrothersfan.com which receives approximately 17,000 hits (now we get over 30,000 people a day!) a day according to their father and web developer; Patrick Santry. As a result the sisters have gained many of their own MySpace fans, with over 6,500 "friends" between the two of them (now over 11,000).
The article goes on to discuss their belief in purity before marriage, encouragement of other teens, and not giving in to temptation.