Prince Philip had a nickname that only his close friends and trusted staff could call him, a leading royal historian has claimed.
According to Adrian Tinniswood, there was a pet name only a chosen few within the household knew about - as well as those who loved the Duke of Edinburgh for many years.
The author of Behind the Throne: A Domestic History of the British Royal Household says they would often call him "P.P" when in private – a shortening, of course, of Prince Philip.
