Selvi Krishna, six, was chosen as Santa’s Special Helper for the annual event.
The youngster was born with achromatopsia, a visual disorder which makes her partially sighted and colour blind.
As a result she loves being outside in the dark, especially at Christmas when the sparkling lights help bring her world to life.
The switching on of the lights at Duke of York Square traditionally sees a youngster participating who has achieved something special, helped others or has a request which Santa can make come true.
Duke of York Square’s Christmas Lights Switch-On event, organised by Cadogan , marks the beginning of festive celebrations in Chelsea.
As well as the magical switch-on moment, visitors enjoyed meeting Father Christmas’s reindeer, festive entertainment and the official opening of the complimentary Santa’s Grotto.
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