Duchess Kate is elegant in royal blue to visit the Imperial War Museum

Ahead of the 100th anniversary of the signing of the World War I Armistice, the Duchess of Cambridge paid a visit to London's Imperial War Museum to learn about its initiatives and document archive.

It was an emotional day for the mom of three, who viewed historical documents on her family's involvement in World War I -- including a letter from the Keeper of the Privy Purse from Buckingham Palace.

Olive Lupton, the duchess' great-great grandmother, had three brothers who all died in the Great War at ages 24, 28 and 31. Lupton was a VAD nurse with the British Red Cross during the war, and later went on to marry Lieutenant Richard Middleton.

The duchess chose a modest dress by her go-to designer Jenny Packham for the occasion, the same one that she previously donned during her royal tour of Canada in 2016. She paired the long-sleeved, royal blue frock with a nude clutch and nude heels.

It's been a busy week for the mom of three, who stepped out on Tuesday for Coach Core.

For more on Kate's visit yesterday, watch the video above!

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