Queen Elizabeth II's grandchildren holding a silent vigil beside her coffin Saturday, September 17, 2022. [AP photo]

All eight of Queen Elizabeth II's grandchildren stood in silent vigil beside her coffin Saturday, capping another huge day in which thousands came to pay their respects. Mourners huddled in a line that snaked across London, enduring the city's coldest night in months and waits that stretched up to 16 hours.

Authorities warned that chillier weather was expected Saturday night. "Tonight's forecast is cold. Warm clothing is recommended," the ministry in charge of the line tweeted.

As U.S. President Joe Biden and other world leaders and dignitaries flew into London ahead of the queen's state funeral on Monday, a tide of people wanting to say goodbye streamed into Parliament's Westminster Hall for another day Saturday. That's where the queen's coffin is lying in state, draped in her Royal Standard and capped with a diamond-studded crown.

The numbers of mourners have grown steadily since the public was first admitted on Wednesday, with a queue that snakes around Southwark Park and stretches for at least 5 miles (8 kilometers).

Honoring their patience, King Charles III and his eldest son Prince William made an unannounced visit Saturday to greet people waiting to file past Elizabeth's coffin, shaking hands and thanking mourners in the queue near Lambeth Bridge.

Later, all the queen's grandchildren stood by her coffin. William and Prince Harry, Charles' sons, were joined by Princess Anne's children, Zara Tindall and Peter Philips; Prince Andrew's daughters, Princess Beatrice and Princess Eugenie; and the two children of Prince Edward - Lady Louise Windsor and James, Viscount Severn.

William, now the heir to the throne, stood, his head bowed, at the head of the coffin and Harry at the foot. Both princes, who are military veterans, were in uniform. Mourners continued to file past in silence.

Harry, who served in Afghanistan as a British army officer, wore civilian clothes earlier in the week as the queen's coffin left Buckingham Palace because he is no longer a working member of the royal family. He and his wife Meghan quit royal duties and moved to the United States in 2020. The king, however, requested that both William and Harry wear their military uniforms at the Westminster Hall vigil.

Before the vigil, Princesses Beatrice and Eugenie issued a statement praising their "beloved grannie."

"We, like many, thought you'd be here forever. And we all miss you terribly. You were our matriarch, our guide, our loving hand on our backs leading us through this world. You taught us so much and we will cherish those lessons and memories forever," the sisters wrote.

Saturday's vigil followed one on Friday in which the queen's four children - Charles, Anne, Andrew and Edward - stood vigil at the coffin.

Edward said the royal family was "overwhelmed by the tide of emotion that has engulfed us and the sheer number of people who have gone out of their way to express their own love, admiration and respect (for) our dear mama."

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