Keira Knightley walked down the aisle on Sunday as a bridesmaid at her brother's wedding.

The star got into the celebration spirit less than a week before Britain's Royal Wedding on Friday to watch her older brother Caleb marry his designer fiancee Kerry Nixon.

The actress donned a purple bridesmaid dress and held a pink and white bouquet for the ceremony at Pollokshields Burgh Hall in Glasgow, Scotland.

The groomsmen and several members of the family wore traditional kilts, to reflect Knightley's mom Sharman's Scottish heritage.

Knightley reportedly took her new boyfriend, Klaxons rocker James Righton, to the nuptials as her guest.

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