Princess Anne's love child
Anne allegedly had an affair with her personal bodyguard Sergeant Peter Cross in 1979.
He later sold his story to the UK newspaper News of the World, claiming he was the first person Anne rang after giving birth to her second child Zara, in 1981, leading to speculation that he is her biological father.
Anne’s marriage to Captain Mark Phillips ended in 1989, with the announcement that they would no longer live together.
They were divorced in 1992.
Duke of Kent's secret children
Prince George, Duke of Kent, was reported to have enjoyed a string of affairs during his life, as well as being addicted to morphine and cocaine.
Brother to Edward VIII and King George VI, it’s rumoured he fathered several children outside wedlock before dying in an air crash during active service in 1942.
The hidden royal son
The Queen’s uncle, Prince John, was born in 1905 and after developing epilepsy at four was hidden away from the palace and sent to live at Wood Farm, a small cottage at Sandringham.
He was ostracised from the royal family and died in his sleep aged 13.
Marina Mowatt's love child
In 1990, Marina Ogilvy – then 26th in line to the throne – shocked Britain when she wed photographer Paul Mowatt while pregnant with their first child, Zenouska.
The first royal birth outside of wedlock in 90 years, Princess Alexandra’s rebel daughter sold her story to a newspaper, claiming her parents urged her to terminate the pregnancy.
For the full story see this weeks issue of New Idea, on sale now.