Queen Elizabeth II, 91, has been on the throne for over 66 years since taking the throne in 1952.

Channel 5 documentary “Elizabeth: Our Queen” has been revealing some of the details after her childhood.

This week’s episode revealed a shocking secret about The Queen and Margaret Thatcher.

The tensions between the two is rumoured to have been a much more “proper relationship” than other Prime Ministers, of which the Queen has seen 12 of within her reign.

Princess Josephine Loewenstein explained on the documentary how her friend Princess Margaret revealed the story behind it.

She said: “I’ve only seen my sister cry once.”

“It was when the Press put all the articles about her not getting on with Mrs Thatcher, that there were daggers drawn.

“It was absolutely not true.”

It is thought that Margaret Thatcher would drink a whiskey after their meetings out of nerves.

Lord Butler explained how she was “in awe” of the Queen, however.

The Queen reportedly once said “Can’t someone tell that woman to just sit down?” when Thatcher stayed at Balmoral and continued to attempt to be the host, despite being the guest.

She the eighth prime minister of the 12 she would see during her reign, yet they were also seen to be rather similar in outlook when it came to leading the country.

Last week, the documentary revealed the fraught relationship the Queen had with her uncle, who abdicated the throne for his wife the Duchess of Windsor.

In 1972, the Queen visited Edward, Duke of Windsor as he was dying from throat cancer.

Royal historian Hugo Vickers said: “With great difficulty he rose from his bed to give his bow because, of course, she was his Queen now, as well as his niece, and it meant a great deal to him that she paid him this final courtesy.”

Ten days later, the Duke died, with the Queen even persuading the Queen Mother to attend despite tensions between the two.