Is Saoirse Ronan in a Twilight spin off?

Just like The Twilight Saga star Kristen Stewart, Saoirse Ronan got her start acting in independent films, most recently in the action flick Hanna. Now, Saoirse is making the leap into mainstream Hollywood also thanks to Twilight author Stephenie Meyer... but she won't be hanging with vampires. Saoirse has been cast in The Host, Stephenie's next big screen adaptation. She will play a freedom fighting teenager and the parasite working to fully take over her body.