Fresh off maternity leave, Kate, who usually favours a more subtle hue for such occasions, stunned in a bold pink Alexander McQueen gown and Philip Treacy hat, while William looked dapper in a dark suit with a blue tie.
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The royal couple were no doubt enjoying not only taking a back seat as guests at the event rather than part of the service.
Kate and Wills also managed to enjoy some kid-free time as Prince George and Princess Charlotte - who were a part of the royal bridal party - and they even managed to sneak in a little PDA.