Paris Hilton is being introduced as lover Benji Madden's wife.
The hotel heiress who started romancing the Good Charlotte rocker earlier this year sparked wedding rumours after Benji's brother Joel called her his "sister-in-law" and Benji was spotted wearing a diamond ring bearing the initials PH.
A source said: "Paris and Benji are inseparable. A lot of people have brushed their romance off as a publicity stunt but Benji is serious about Paris and he has discussed marriage plans with his brother - which is why Joel called her his sister-in-law. He said it in a jokey way, but it sounds like it is just a matter of time."
Joel, who is engaged to Paris' best friend Nicole Richie, is said to be concerned his brother is rushing into marriage because he and Nicole are planning to wed.
Joel, who has a three-month-old daughter Harlow with Nicole, is also reportedly worried that Benji is on the rebound following his split from his fiancee, Australian model Sophie Monk.
The source added to Britain's Daily Mirror newspaper: "Benji was engaged to Sophie just a few days before he started dating Paris, so Joel just wants to make sure he knows what he is doing."
Meanwhile, Paris and Benji have been accused of being in a hit and run incident against a photographer. Glen Gurniak filed a lawsuit against the couple, claiming Benji drove over his foot while Paris was in the passenger seat as they left a Hollywood club.
Gurniak said: "There were too many people that side of the car so he swung the wheels in my direction on the other side of the car and got my foot trapped under the wheel.
"I yelled at him, 'Dude, you've pinched my foot under the wheel, don't drive, don't drive.' He turned and looked at me out of the window and then just drove."