King Charles III's coronation: The biggest moments of the historic event

Prince Harry did not join his family for the traditional balcony appearance at Buckingham Palace following the coronation service.

Harry was the only member of his immediate family missing from the moment, with Charles and Camilla there as well as William and Kate and their three children.

As a non-working royal, Harry also did not join his family for the carriage procession from Westminster Abbey to Buckingham Palace.

Harry attended the coronation alone, with his wife Meghan and their two children, Archie and Lilibet, staying home in California.

Sources told ABC News royal contributor Omid Scobie that Harry will be heading back to the U.S. soon after attending his father's coronation.

The date of the coronation coincides with Archie's birthday, who turns 4 Saturday.

The current and future generations of the monarchy stepped out on the balcony, represented by Charles, William and George -- the king and first and second in line to the throne, respectively.

Joining the king and future kings on the balcony were Camilla, Kate, Charlotte and Louis, and other members of the royal family.

Also standing alongside Charles and Camilla were the young men who served as their Pages of Honour.

Charles' pages include his grandson George as well as Lord Oliver Cholmondeley, Master Nicholas Barclay and Master Ralph Tollemache.

Camilla's four Pages of Honour are her grandsons, Master Gus Lopes and Master Louis Lopes and Master Freddy Parker Bowles, and her great-nephew Master Arthur Elliot.

After a short pause, Charles and Camilla returned for an encore appearance, with just the two of them on the balcony, waving to the cheering crowds below.

Charles and Camilla as well as William, Kate, George, Charlotte and Louis have an up-close view from the Buckingham Palace balcony of a military flypast.

Aircraft from the Royal Navy, British Army and Royal Air Force are flying over The Mall in central London.

The flypast was shortened from the planned six minutes to just over two minutes in length due to rainy weather in London Saturday.

Sources told ABC News royal contributor Omid Scobie that Prince Harry, Duke of Sussex, will be heading back to the United States soon after attending his father's coronation in London on Saturday.

"I'm here on the Duke of York steps, we've just seen the procession go back to Buckingham Palace and for Prince Harry, the Duke of Sussex, that probably brings his very quick trip to London to an end," Scobie said. "We saw him arrive on Friday evening getting ready, of course, for the big day to support his father at the coronation ceremony."

"But, of course, he also has duties back in Montecito, California, and sources close to the duke say that it is going to be an in-and-out trip for him," he added. "Just here to be part of that moment in Westminster Abbey, support his father and then be back at home to support his own family in Montecito."