He was playing madly with his brother, I could see they were scuffling over something so I went over to investigate, and they were playing with a smallish stone (maybe about 1/2 the size of a squash ball). Before I could get it off them, one of them had swallowed it.
Ought I to take him to the vet or anything or will it just pass through? It looked smooth, not sharp. Silly dog.