She styled the look further with a coordinating hat, delicate off-white Jimmy Choo heels and an ivory satin box clutch by the same brand.
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Markle's appearance on the Palace balcony will be her second following her Buckingham debut at Trooping the Colour at the beginning of June.
Chris Jackson via Getty Images The rest of the royals watch the flypast.
Baby Prince Louis was christened overnight at The Chapel Royal, St James's Palace, and while we were incredibly excited to get a glimpse of the young prince, we were even more excited to see what his mother, Kate Middleton would wear.
Buckingham Palace told the Press Association in a statement that the two had previously agreed to skip the christening, and their absence wasn't related to health problems.
At Prince Louis' christening on Monday 9 July Meghan paired her khaki dress with a matching pair of court shoes.