Credit: PA Photos /Landov

Taking a page from her younger sister's style playbook, Kate Middleton attended a charity gala in London on Thursday night in a head-turning red evening gown.

The dress, which was designed by Beulah London and featured a low neckline and billowy long sleeves, showed off her slim figure.

Prince William and Duchess Catherine were the guests of honor at the black tie event, held at St James Palace by 100 Women in Hedge Funds and helped raise $1 million for the Child Bereavement Charity.

The Royal duo, both 29, recently opened the Oak Centre for Children and Young People at The Royal Marsden Hospital in Sutton, Surrey.