In an old image posted online of Prince Harry's future wife, Meghan Markle, 16, can be seen beaming as she poses with then-boyfriend Luis Segura.

At the time, Meghan, now 38, was attending Immaculate Heart High School, according to The Sun.

For the 1997 dance, she chose to wear a slinky black dress, choker and stylish up-do.

The photo appears to have been taken during the festive season since the couple are standing in front of a Christmas tree.

According to the image caption, "16 year old Meghan Markle [poses] with her first boyfriend Luis Segura at a high school Christmas dance in 1997".

The post has received more than 63,000 'likes' - and many social media users were in disbelief at how little the Duchess appears to have aged.

One person wrote: "She still looks the same, good genes."

Another commented: "She hasn't changed."

A third shared: "Princess Meghan was a gorgeous teenager."

And a fourth added: "You could have told me that was taken last year and I'd wholeheartedly believe you."

Last month, Meghan's high school teacher said she was "always a leader among her school friends" and "stood up for the underdog".

Ilise Faye - who taught the Duchess until she was 13 years old - added: "School was important to her, learning was important and she had a voice."

This story first appeared in The Sun and is republished with permission.