The royal, who is expecting her first child next year, reposted a photo that the US singer originally shared on her Instagram account last month.
Eugenie wrote in a caption: "I thought this was super cool of @selenagomez to show she's confident of who she is and what she went through after finding it difficult to show her scar. Let's be proud of our uniqueness".
Sharing a photo of herself in a blue swimsuit, Selena wrote at the time: "When I got my kidney transplant, I remember it being very difficult at first showing my scar. I didn’t want it to be in photos, so I wore things that would cover it up. Now, more than ever, I feel confident in who I am and what I went through...and I’m proud of that."
The royal has been encouraging her followers to proudly share photos of their own scars, some of which she has re-posted on her Instagram Stories.
Eugenie reposted one of Selena's Instagram photos
Eugenie was told she would have to have life-changing surgery on her back when she was 12 years old. She had titanium added to her spine to rebuild it as a result of a curvature.
The Princess, who will celebrate her second wedding anniversary with husband Jack Brooksbank on Monday, wore a low-back dress on her big day to proudly show her scoliosis scar.
Eugenie proudly showed her scar on her wedding day in 2018
The 30-year-old is a patron of the Royal National Orthopaedic Hospital where she underwent her operation, and previously revealed how her scar from the life-changing surgery inspired the design of her wedding dress.
Speaking to The Telegraph, Eugenie said: "After one or two initial meetings where I said I wanted to show my back and scar, we had a fitting and in their first attempt at the shape and design of the dress, they got me and the vision in one."
She added: "From there, we realised that the back of the dress was the centre point and a veil would take away from the scar and the beautiful design they had created."
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