The legendary makeup artist gives us all the details on the red carpet look.

A two-piece dress, the top was styled like an oversized button-down that was tied just below her chest.

McGrath tells Byrdie that “Sienna Miller’s pregnancy glow became the ultimate muse.

Sienna Miller on the red carpet at Vogue World in London in a two piece Schiaparelli dress with her baby bump exposed

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And the “majorness” of the event is no joke.

Sienna Miller on the red carpet at Vogue World in London in a two piece Schiaparelli dress with her baby bump exposed

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Up close of Sienna Miller’s makeup done by Pat McGrath on the red carpet of Vogue World in London with gold dangle earrings and pink lips

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