The first and only time in her life Queen Elizabeth II broke royal protocol

As the gun carriage bearing Princess Diana's coffin passed by, a figure dressed in black bowed her head.

It marked the first and only time in her life that Queen Elizabeth II would ever bow to another person in public - breaking all the rules.

Following Diana's death on August 31 in 1997, the monarchy was changed forever. 

Suddenly, the Queen's priority was to be a grandmother to Prince William and Prince Harry instead of putting her duties first.

But once the shock passed, she came out of Buckingham Palace to join the crowds gathered to watch Diana's coffin as it made its way to Westminster Abbey - and she bowed her head.

The monarch had been at Balmoral with her family, along with William and Harry, when the call came from Paris at 4.15am that Diana was dead.

While William and Harry were both asleep, Her Majesty decided not to wake them immediately and ordered staff not to turn on TVs or radios in case they heard anything.

Just after 7am, Prince Charles woke them up and broke the news.