The hospital he is in now has a community garden beside it, maintained by volunteers. It has a hen run with a couple of ducks and several hens (and a couple of tiny chickens today, too), which apparently he really enjoys visiting so we spent most of our visit this afternoon sitting there. C went to investigate the small greenhouse (really a section of polytunnel) and came back telling me he had seen the most beautiful butterfly. There are several ceramic sculptures in the garden, and initially he thought the butterfly too was a piece of art - until it moved. I went off to look, and at first I only saw it with the wings closed - which was indeed very beautiful. It's a small butterfly - not much bigger than the top joint of my thumb when the wings are folded closed.
And then it opened them to reveal the most beautiful blue. It's a (not very common) Common Blue.
Unfortunately I had left my camera in the car, and had to make do with my phone, so the quality isn't great.
The foliage is fennel, I'm not quite sure what the flower was...