The Queen, Charles and William 'always travel with a bag of their own blood'

The Queen, Prince Charles and Prince William always take a vital essential on their royal tours with them - a supply of their own blood.

The Sun’s former royal editor Duncan Larcombe tells Yahoo UK’s ‘The Royal Box,’: “If it’s the Queen, Prince Charles or Prince William, they’ll have the royal physician with them, with a bag full of their own blood, just in case something happens.”

With Charles and Camilla going to New Zealand, Kate and William set to travel to Pakistan and Meghan and Harry heading to Africa this autumn - who is in their royal entourage?

The Sunday Times' royal correspondent Roya Nikkhah explains: "It tends to be between 12 - 14 in the entourage. It tends to be three press secretaries, a private secretary, sometimes an assistant private secretary will go as well, a hairdresser, a valet, a digital person who assists with communications."