Meghan Markle's first engagement with Queen Elizabeth to take place before wedding

After making their engagement debut in February, the fabulous four — the Duke and Duchess of Cambridge, Prince Harry and Meghan Markle — will reunite on March 12 for Commonwealth Day. The Suits alum is set to carry out her first public engagement with her future grandmother-in-law, Queen Elizabeth, attending the Commonwealth Day service at Westminster Abbey. The royal bride-to-be will be joined by her fiancé Prince Harry, as well as Prince William, Kate Middleton, Prince Charles, the Duchess of Cornwall, the Duke of York, the Princess Royal and the Countess of Wessex at the royal family affair.

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VIEW GALLERY Meghan will attend her first engagement (the Commonwealth Day service) with Queen Elizabeth and other royal family members on March 12 Photo: Anthony Devlin - WPA Pool/Getty Images

The service is the largest annual inter-faith gathering in the UK in celebration of Her Majesty's lifetime commitment to the Commonwealth. This year's Commonwealth Service will feature a special musical performance by former One Direction member Liam Payne. 

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The outing will mark Meghan's second engagement with William and Kate. The TV star attended her first public event with the Duke and Duchess on February  28 at the first annual Royal Foundation Forum. “We have different opinions and they work really well [together],” Harry, 33, said. “Working as family does have its challenges; of course it does." “[I think] the fact that everybody is laughing shows they know exactly what’s it like,” he added. “But we are stuck together for the rest of our lives.” To which Meghan, 36, replied, “Togetherness at its finest.”

VIEW GALLERY The foursome attended their first engagement together on February 28 Photo: Chris Jackson - WPA Pool/Getty Images

The Royal Foundation was set up by the Duke of Cambridge and Prince Harry as the main vehicle to pursue their charitable interests. The Duchess of Cambridge became a Patron in 2011, and Meghan will soon become the fourth Patron after her May 19 nuptials. 

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During the forum, Harry expressed his excitement over working with his future spouse. He said, “I am personally incredibly proud and excited that my soon-to-be wife, who is equally passionate about seeing positive change in the world, will soon be joining us with this work.”