Sarah, Its a nice shot of William.
The metering and focus is spot on, however it needs sharpening and the composition needs tweeking.
Your subject should idealy be a 3rd in from the left or right from the edge of the frame, but this doen't always have to be the case.
The landscape format for this image doesn't work as there is nothing in the background of interest, so there is no real need to include the hedging.
Portrait mode would suit this image, with a selective crop and a slight bit of unsharp mask, your subject can be brought out from the background.
Here's a Before and after example with unprocessed and processed images.
