Queen Elizabeth II turned 93 on Sunday and her grandson and his wife, Prince Harry and Meghan Markle, were quick to pay tribute to Her Majesty on Instagram.

Ahead of the royal's Easter service, the couple posted a series of pics of Queen Elizabeth, along with the message: "Happy Birthday Your Majesty, Ma’am, Granny. Wishing you the most wonderful day! ?Harry & Meghan."

Among the photos posted is a black-and-white photo of the queen at a young age as well as some flashback images of her with Harry and his brother, Prince William, when they were children.

There are also pics of Queen Elizabeth with Meghan and Harry. 

On Sunday, Harry joined his grandmother for Easter service at St. George's Chapel at Windsor Castle, but Meghan, who is set to give birth any day now, was not in attendance. Prince William and Kate Middleton were also at the service, and their own birthday wish for the queen on Instagram.

Harry, 34, and Meghan, 37, joined Instagram at the start of April and already have over four million followers. Fans have speculated that the Duchess of Sussex is overseeing the social media account herself. 

Here's a look at the clues that suggest Meghan might be posting her own Instagram pics:  

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