The inspirational TV presenter and author has always kept her relationship well away from the spotlight, but over the weekend she couldn't resist posting a sweet picture to Instagram after James presented her with an engagement ring.
Katie and James became engaged in December but it appears Katie had to wait until this weekend to get the diamond.
She captioned her photo: "He put the official ring on it!"
Katie also gave fans a close-up of her beautiful ring, saying: "It's everything I wanted and more, thank you @lewismalka for designing such a beautiful and sentimental piece for me. Can't stop looking at what I used to class as my bad hand- not anymore :)#engagement #wedding."
Fans were quick to send congratulatory messages and well wishes, prompting Katie to say: "Thank you for all the wonderful tweets. I know I always say but it truly is so lovely to read all the kind genuinely happy for us messages!"
Katie and James are parents to daughter Belle, ten months.
Bodyshockers host Katie has said she wants Belle to walk her down the aisle when the couple tie the knot.
"Belle is part of a whole new world I never thought would be accessible," she told The Mirror.
"Knowing we're going to be a full family unit has really made my life complete. We've been watching her trying to stand up and walk and saying it would be great if she could walk down the aisle with us. Plus I think it will be nice for Belle that we'll all have the same surname as a family. I can't wait for it all to be official."
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