Sienna Miller in new love triangle

Sienna Miller dating married Getty Oil heir?

A month after ending her relationship with actor Rhys Ifans, Sienna Miller has reportedly found herself in a tricky love triangle with a married American actor, who also happens to be heir to the multi-million pound Getty fortune.

The actress's budding relationship with Balthazar Getty, a 33-year-old father of four who plays Tommy Walker in the hit US show Brothers and Sisters and whose great-grandfather was the late oil tycoon John Paul Getty, came to light this weekend after the pair were photographed together in LA.

Sienna flew to LA last Monday, and was seen with Getty at a petrol station on Tuesday. On Thursday night, they met for dinner at an Italian restaurant in Beverly Hills, and the day after they were spotted together at LA's Chateau Marmont hotel.

It is thought Sienna's ex, Matthew Rhys – who co-stars with Getty on Brothers and Sisters – introduced the pair last summer.

Getty's wife of eight years, designer Rosetta Millington, is said to have flown to Italy with their four children - Cassius, seven, Grace, six, Violet, five, and eight-month old June Catherine – following the revelations.

It is thought Matthew introduced the pair in Prague when Sienna was filming GI Joe. A source told the Mirror: 'Sienna got to know Balthazar through Matthew and they hit it off. They have grown incredibly close. He secretly flew to London and Prague to be with her. She has spent last week in a Hollywood house with him.'

Before he was married, Balthazar was linked to Drew Barrymore and Milla Jovovich.

SEE EXCLUSIVE PICS OF THE PAIR TOGETHER HERE

SEE MORE SIENNA MILLER PHOTOS HERE