You can just see her, in this Getty video, sat beside him in the car as they leave the Games.

https://www.gettyimages.co.uk/detail/video/king-charles-iii-departs-the-2026-mey-highland-games-at-news-footage/2288642128?slot=8&adppopup=true

The King spending time at the Castle of Mey, I'll bet as he does each summer. I don't blame him. The location is breathtaking and the home/castle is gorgeous. The late QEQM loved it and so does her grandson. If you were very wealthy and wanted somewhere to totally get away, this would have been the spot. QEQM and Charles knew that.