Prince Philip stopped the press from taking the Queen's photo right after she became the monarch, according to the late royal's cousin

• Prince Philip's cousin Pamela Hicks spoke about the moments after the Queen took the throne. 
• Hicks, a former lady-in-waiting, said Philip's aides warned photographers against taking photos. 
• Her Majesty became Queen automatically upon the death of her father.

This Sunday marks 70 years since Queen Elizabeth II became the monarch.

Her Majesty was informed that her father, King George VI, had died when she was on a royal tour of Kenya in 1952. His death resulted in the Queen's automatic accession to the throne.

Somebody who was there to witness the historic moment was Lady Pamela Hicks, Prince Philip's cousin and a former lady-in-waiting to the Queen. Hicks spoke of the experience on Friday alongside her daughter India Hicks during a virtual event about the Queen's upcoming Platinum Jubilee, entitled "70 Years of Duty and Friendship."

Hicks said she was with the Queen when they were told the news of her father's death. She said that when they arrived at the airport to travel back to the UK, Prince Philip's equerry asked members of the press not to photograph her because she was mourning. 

"So when we arrived at the airport, the press were standing with their cameras at their feet," Hicks said. "Can you imagine them doing that now?" 

To mark the Queen's Diamond Jubilee in 2012, Buckingham Palace released previously unseen footage of the Queen on the flight back to the UK after learning her father had died. 

The photo, taken by Philip, showed the monarch wearing dark colors and staring into the distance.

Hicks also shared her initial reaction to learning of the Queen's accession. 

"I thought, 'God, this 25-year-old girl and her husband, who should no doubt get to the top of his profession in the navy, now he will have to give up his job, and walk two paces behind her,'" Hicks said. "'And her children will never have a private life again.'"

While February 6 marks the anniversary of the Queen's accession to the throne, she wasn't officially coronated until the following year, on June 2, 1953.

Her Majesty will celebrate her Platinum Jubilee in June with a four-day public holiday in the UK. 

India Hicks previously told Insider that Her Majesty rarely celebrates the day of her accession out of respect to her late father.

"It may be the day that she became Queen, but it was also the day that her father died," she said to Insider. "She was very, very close to him. So I think you're probably dealing with the mixed emotions there."