Sienna Miller, 42, dazzles in sheer gown as she brings boyfriend Oli Green, 27, and lookalike daughter Marlowe, 10, to Horizon: An American Saga premiere at Cannes Film Festival

Sienna Miller was supported by her family on Sunday night as she attended the premiere of her film Horizon: An American Saga at the Cannes Film Festival with her boyfriend and daughter.

The actress, 42, put on an ethereal display in a semi-sheer dress as she arrived on the red carpet with boyfriend Oli Green, 27, and lookalike daughter Marlowe, 10.

It marks Marlowe’s first-ever red carpet appearance, with her famous mother only showing her face for the first time in a spread for Vogue in July 2020.

Sienna shares Marlowe with her ex Tom Sturridge, with whom she dated from 2011 to 2015.

While the movie star only recently welcomed a second daughter and first child with Oli in January.

The actress, 42, put on an ethereal display in a semi-sheer dress as she arrived on the red carpet with boyfriend Oli Green, 27, and lookalike daughter Marlowe, 10

It marks Marlowe’s first-ever red carpet appearance, with her famous mother only showing her face for the first time in a spread for Vogue in July 2020

Sienna held her eldest child as Marlowe and Oli supported her at the premiere of her new epic western film.

The Anatomy of a Scandal star turned heads in a flowing lavender dress with layers of ruffles.

The sheer material of the draped dress allowed a glimpse of Sienna’s incredible figure in a plunging playsuit underneath.

To add a touch of sparkle to the ensemble, the Golden Globe nominee wore a diamond necklace.

Sienna added silver strappy heels to give herself a few extra inches and a bright pink lipstick for a pop of color.

While daughter Marlowe looked like the spit of her beautiful mother, dressed in a sweet pink dress with a big bow.

Beside them, Oli looked typically dapper in a black suit, white shirt and navy blue tie, while wearing brown-framed sunglasses.

Sienna was soon joined on the red carpet by her co-stars, including the film’s co-writer, director, producer and lead actor, Kevin Costner.

Sienna shares Marlowe with her ex Tom Sturridge, who she dated from 2011 to 2015, and only recently welcomed a second daughter and first child with Oli in January.

The Anatomy of a Scandal star turned heads in a flowing lavender dress with layers of ruffles. The sheer material of the draped dress allowed a glimpse of Sienna’s incredible figure in a plunging playsuit underneath

To add a touch of sparkle to the ensemble, the Golden Globe nominee wore a diamond necklace. Sienna added silver heels to give herself a few extra inches and a bright pink lipstick for a pop of color

Sienna was soon joined on the red carpet by her co-stars, including the film’s co-writer, director, producer and lead actor, Kevin Costner.

Kevin, 69, looked more handsome than ever in a black three-piece suit, including a waistcoat and matching bow tie

Like Sienna, he made the premiere a family affair by also bringing his daughter, youngest child Grace, 13 years old

The Oscar winner is a father of seven: he shares Annie, Lily and Joe with ex-wife Cindy Silva, son Liam with ex Bridget Rooney and Cayden, Hayes and Grace with his second ex-wife, Christine Baumgartner.

Kevin, 69, looked more handsome than ever in a black three-piece suit, including a waistcoat and matching bow tie.

Like Sienna, he made the premiere a family affair by also bringing along his daughter, youngest child Grace, 13.

The Oscar winner is a father of seven: he shares Annie, Lily and Joe with ex-wife Cindy Silva, son Liam with ex Bridget Rooney and Cayden, Hayes and Grace with his second ex-wife, Christine Baumgartner.

Isabelle Fuhrman, Abbey Lee and Jena Malone also appeared glamorous on the red carpet, all opting for semi-sheer and pastel-colored dresses.

Horizon: An American Saga chronicles a multifaceted, 15-year period of expansion and settlement of the American West before and after the Civil War.