Lady GaGa and Tony Bennett brought their ‘Cheek to Cheek’ show to London’s Royal Albert on Monday evening, for a night of classic songs and old fashioned glamour all in aid of children’s charity WellChild.

Tony Bennett and Lady GagaGaga and Bennett onstage together at the Royal Albert Hall.

The charity, which supports seriously ill children and their families across the UK, sent along royal patron Prince Harry to enjoy the evening’s festivities and the 5th in line to the throne managed to get up close and personal with the two singers.

Meeting the pair before the gig, the Prince was told, “We think you are fantastic,” by Gaga, while Bennett added "Your mum was a good friend of mine, I did many benefits with her.” Harry was also joined at the gig by supporters of the charity as well as nurses and their families who were given seats in the Royal Box for the performance.

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While Bennett and Gaga might seem like an unlikely duo to some, the pair who share a sixty year age difference, have bonded over a mutual love of old standards. Last November they released their Grammy winning collaborative album Cheek to Cheek and over the past few months they’ve been enjoying bringing the songs to life onstage together.

Tony Bennett and Lady GagaGaga and Bennett have a unique chemistry despite their age gap.

Writing in The Guardian, Caroline Sullivan described the onstage relationship between the two as ‘mutually beneficial’. Adding. ‘He gives her gravitas, she gives him energy – and the chemistry is real.’

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The Telegraph’s Neil McCormack also saw the pair's unique chemistry as he wrote that the ‘unlikely duo seemed to be having most fun on swinging numbers full of flirtatious comedy and bravado but the union actually made most sense on deep ballads…when the age gap of voice and style was bridged by pure emotion.’

The concert is reported to have raised more than £100,000 for WellChild, with another sold out performance scheduled for tonight (June 9th). "WellChild is thrilled that Lady Gaga and Tony Bennett are supporting WellChild through this concert," the charity's chief executive Colin Dyer said in a statement. "The proceeds will be a massive boost to our work to support seriously ill children and their families across the UK."

Tony Bennett and Lady GagaThe pair will play a second concert tonight (June 9th).