Meghan Markle and Prince Harry joined their in-laws Kate Middleton and Prince William together with the rest of the royal family for the Commonwealth Day service at Westminster Abbey.

This was the Duke and Duchess of Sussex's final engagement before they formally step down as senior members of the royal family on April 1, 2020.

Walking hand in hand inside Westminster Abbey, Meghan donned an elegant green dress with a cap while Prince Harry wore a blue suit with a white shirt and pale blue tie. 

Unlike last year, Meghan Markle and Prince Harry did not wait for Queen Elizabeth II on the premises of the church to join her in a procession through the aisle of the abbey. Instead, they swiftly entered and sat in the second row just beside Prince Edward and Sophie, Countess of Wessex.

The Duke and Duchess of Cambridge were expected to join the Commonwealth Day procession as the start of the service but later, it was also reported that they would also head straight to their seats. 

Beside them was Prince Charles, Camilla, Duchess of Cornwall and Queen Elizabeth II. 

While fans marveled over the fashion scene at the service, others could not help but talk about the interaction of the "Fab Four." 

Us Weekly reported that while the Duke and Duchess of Sussex smiled and said hello, their in-laws were quick to take their seats following a brief acknowledgment of the pair. 

The former "Suits" actress mouthed "hi" to their in-laws as they took their sit in front. Kate said "Hello Meghan" with a smile, while Prince William said, "Hello, hello." Prince Harry smiled back at his older brother and said "Hello," who seemed to ignore him.

But that was the end of their awkward interaction. It was an "awkward sibling reunion" according to body language expert Judi James.

Prince Harry's tension was "palpable," as his older brother seemingly failed to greet his brother. James added it was not the reunion royal watchers are waiting for. 

"When Harry arrived, the minute he and Meghan had to drop hands, he immediately reached for his wedding ring which is a self-comfort," James pointed out.

"Even when she was beside him after they had stopped holding hands, he was missing her, needing her support." 

She also noted that as the Duke of Sussex walked up the aisle, he and his wife waved at the children but Prince Harry's face was tense and not smiling. 

Once Prince William and Kate went away after the service, James saw a different kind of Prince Harry afterward. 

"With the other royals gone Harry and Meghan became an animated, tactile double-act again," the body language expert furthered,

Prince Harry was seen chatting to Craig David as if he was his old friend, while Meghan was leaning forward to touch Anthony Joshua on the arm to congratulate him for his speech. 

At the party after the service, James noted that Prince Harry was laughing and joking with the people and looking relieved, far more relaxed while holding his wife's hand again. 

"He looked like a man who felt he's got the most difficult moments over and who could now return to being 'Just Harry' again with his wife and son," James ended.

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