What is it like to make the Queen's hats?

In her long reign, the Queen has lived through 12 prime ministers, 12 US presidents and seven Popes, has been on official visits to 116 countries, answered more than 3.5 million letters and sat for a staggering 129 portraits.

She has also worn a lot of hats - possibly more than anyone else in the world.

Her official milliner, Rachel Trevor-Morgan tells Sophie Raworth what it's like to make hats for the Queen.