Kate Middleton in blue polka dot dress by Alessandra Rich for Big Lunch

William and Kate surprised locals by dropping in on a street party in Kensington, London on Sunday. The Duchess looked beautiful in a blue polka dot dress

Princess Kate rocks polka dots in show-stopping Alessandra Rich dress

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Kate Middleton's Alessandra Rich Azure Blue Polka Dot Dress

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Kate Middleton in blue polka dot dress by Alessandra Rich for Big Lunch

Alessandra Rich polka dot dress beloved by celebrities

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I tried to dress like Kate Middleton by shopping in Primark and I almost succeeded' - Amber-Louise Large - MyLondon