Extend Sheep Photo Seamlessly

I have a single-frame JPG featuring a sheep. I need the canvas extended upward so that the overall height is roughly twice the current size, while the width and the sheep itself remain untouched. The new upper area should look like a natural continuation of the existing background—no visible seams, cloning marks, or added graphic elements. Please keep everything plain; no text, logos, or decorations.

Deliver the finished file in high-resolution JPG (same or better quality than the original). If you work in Photoshop or a similar tool and can share a layered file for future tweaks, that’s a plus, but the flattened JPG is the required deliverable.