Duchess of Cambridge told George, Charlotte & Louis they couldn't come to Royal Variety performance – 'Not on a school night'

The Duchess of Cambridge, 37, attended the Royal Variety performance of ‘Mary Poppins’ last night.

But despite the family-friendly nature of the occasion, her own three children - Prince George, 6; Princess Charlotte, 4; and Prince Louis, 1 – were absent from the Palladium Theatre event.

Duchess Kate explained why during a conversation with the show’s performers Petula Clark CBE, Zizi Strallen and Charlie Stemp.

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“I love Mary Poppins,” said Prince William, 37, and the duchess added to this that the children had been excited to hear their parents were going to the performance, and asked to come.

However, the duchess was compelled to refuse, telling the children: “Not on a school night.”

While Prince Louis is too young to attend school, Prince George and Princess Charlotte both attend St Thomas’s Battersea school. Charlotte joined her elder brother at the preparatory school in September this year.

For last night’s event, the Duchess wore a bespoke, floor-length, lace dress by Alexander McQueen. She paired the gown with pearl Erdem earrings, which the 37-year-old previously wore to open the new Photography Centre at the V&A in October 2018.

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The Royal Variety has been attended by members of the Royal Family since 1912. Last year, Prince Harry and Meghan Markle, pregnant with baby Archie at the time, represented the monarchy.

The Queen is a patron of the Royal Variety – which is dedicated to giving support to those who have professionally served the entertainment industry and find themselves sick, impoverished or elderly.