I came upon them grazing on the front lawn.
My daughter explained that after tacking up, she'd let George graze for a while. Then he had been rather disgruntled when the subject of mounting came up. Presumably he resented having his grazing interrupted, and she reasoned that if she let him go right back to grazing after she got up, he would have a less dim view of the matter in future. Makes sense to me.
This is his you-are-a-mean-girl-to-make-me-stop-eating face. However, he cheered up quickly and they set off down the drive.
There were no further arguments, and she let him stop for a quick nibble half way down to the road.
Then off they went for their ride. My daughter told me afterwards that he had been a little jumpy and kept wanting to canter, which I reckon is about normal for a young horse on a brisk windy day. They looked relaxed when they returned.