Paris Hilton and Benji Madden recently began dating and sources say they are already getting serious. The pair each wear diamond rings featuring the other’s initials.

Hilton and Madden were in Las Vegas this weekend where they celebrated the ‘Good Charlotte’ rocker’s 29th birthday. Witnesses say they were acting “lovestruck.”

Friend’s of the socialite say she is “completely at peace with Benji.” They were introduced by Hilton’s pal Nicole Richie, who is engaged to Benji’s twin brother Joel Madden.