Dog-Walking Styles of the StarsBlake Lively and Penny are on set, Carrie Underwood keeps it casual in sweats, and Jerry O'Connell jogs

Credit: Startraks, Pacific Coast News, Splash News Online

Updated: Wednesday Jan 12, 2011 | 06:00 AM EST

BLAKE LIVELY

The Gossip Girl star keeps her toy poodle Penny on set. Whether they're emerging from Lively's trailer or sitting down between takes, they're always in step.