No rest for the royals, eh?

William and Kate had a rare late night out in London last night after their busy days.

Kate had been touring the North East, alone, as William was attending the funeral of his beloved nanny, Olga Powell.

But, back in London after their daily duties came to an end, William and Kate ventured out to private London club Loulou's.

The Duke and Duchess were joined by Kate Middleton's sister Pippa for their evening out, as well as Prince William's cousin Princess Eugenie.

'Nobody knew they were coming and then at 10pm they were swept in through a back door,' one clubber told the Mail.

'They stayed for about couple of hours.'

While Prince William looked super-smart in a navy jacket and trousers, Kate chose a chic black dress - with a slightly higher hemline than we're used to seeing on the Duchess - and knee-length black coat.

The couple were spotted leaving the venue at midnight, accompanied by their royal protection officers.