(Cover) - EN Showbiz - Sienna Miller reportedly helped Robert Pattinson and Kristen Stewart rekindle their romance.

The Twilight stars have experienced a rough patch this year after Kristen cheated on Robert with married film director Rupert Sanders. They are now trying to work things out, with Sienna apparently instrumental in the process.

The British actress is engaged to Tom Sturridge, who is good friends with Robert. It means she has got to know the actor and was a shoulder for him to cry on during his romantic woes.

"Sienna has been with Tom [Sturridge] for 18 months and Tom and Rob have been friends since school," an insider told Heat magazine. "They've all been close for a while, particularly as Tom and Kristen filmed On the Road together."

Robert and Kristen have been seen out together in Los Angeles recently and will shortly commence promotional duties for the last Twilight movie Breaking Dawn - Part 2.

They are reportedly determined to make their romance work.

"They love each other very deeply. All of us knew that they wouldn't be apart for long after the Rupert thing," a source explained. "It's like they're addicted to one another - they can't be happy without each other." (C) Cover Media