I remember my son being ill a couple of years ago, I think he had flu, and I managed it at home and kept his sugars down (his sugars were pretty good actually), then he started complaining of pains in his back, and I tested for ketones and he had a high level, I took him straight to A and E, where after an immensely long wait, a lovely consultant would not let him go home until they had flushed the ketones out! they put him on a drip to do that, so it seems strange to me that they let a toddler go home like that. Happily everything turned out ok for him.