It was the charming moment that stole the show as cheeky Mia stood proudly and clung onto her great-grandmother's purse like a prized possession.
And in a new interview with Good Morning Britain Mike Tindall reveals the endearing turn of events all fell into place by chance.
"It just happened at the right time. She was being a bit naughty,” the proud dad revealed.
“The Queen got it quite right when she told her: 'Just hold the handbag now' and she did that. It ended up being a great photo for her.”
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As we all know, the end result was utterly gorgeous and it's a photo Mike and the royal family will cherish forever.
"It just turned out to be the right photo at the right time and it will be something we'll always cherish, I think," Mike said.
Mia was joined in the photo by the queen's other great-grandchildren, Prince George and Princess Charlotte, Savannah and Isla Phillips and two of her grandchildren, James, Viscount Severn and Lady Louise Windsor.
The adorable two-year-old became an instant sensation, with royal watchers adoring the fact she was holding the fashion accessory.
"Mia Tindall, two, well and truly stole the Queen's thunder in the Annie Leibovitz portrait," one royal watcher tweeted, while another wrote: "I cannot explain how obsessed I am with Mia Tindall RN. This is how I hold my bag on the Tube out of fear."
The 37-year-old dad also revealed how Mia holding onto the bag was unplanned.
“The moment with Mia was completely spontaneous, it was not staged at all. She just picked up her great-granny's handbag and that was it."
Mike married Zara Phillips in 2011 and the pair became first-time parents to Mia in 2014.
The hubby to Princess Anne’s daughter spoke about how as a parent, he and his wife encourages Mia to embrace her own self.
"She's got quite a little personality on her, and we encourage that."