"Their shared laughter and proximity speaks volumes about Meghan's acceptance by the queen but also of how well they get along", he said.
However, editor-in-chief at Majesty magazine Ingrid Seward said that once formalities are out of the way Meghan can refer to the Queen as something else.
This was Markle's first official day of solo appearances with Queen Elizabeth since becoming a part of the royal family.
"The role she's taken on is very austere, it's very serious and I think there's a great weight that she has acquired through that and I think she takes it very seriously".
The duchess sat next to the queen for the performance. The queen and the former actress rode the royal train to the city of Chester, in northwest England, for a busy day of events.
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While preparing to leave, there appeared to be some confusion as to who was supposed to get into the vehicle first, with Markel interrupting the Queen when she began to get in. After a performance by some of the local children, the Queen formally opened the bridge.
"This hand-to-ear touch looks like a partial cut-off gesture, meaning it is a slight barrier that is formed when she is under scrutiny or pressure". Good question: It's actually a multi-million dollar form of transport that's only available to the queen, Prince Philip, Prince Charles and Camilla. The American-born Meghan also didn't wear a dress that was too revealing, unlike the off-the-shoulder designer ensemble she donned at last weekend's Trooping the Colour at Buckingham Palace.
Markle and the Queen marked the opening of the Mersey Gateway Bridge, a new six-lane toll bridge that connects the towns of Runcorn and Widnes.
Psychotherapist Toby Ingham added: 'The body language of the Queen and Meghan is warm, friendly, they look to be enjoying the time they are spending together.
"It might have been the reason why Meghan looked far more nervous on this outing than we've seen her before".