My daughter's (2yrs) been sick since the beginning of the week - first with painful mouth ulcers (thanks for the responses on that post) but now it's turned into a vomiting virus that's just wiped her out. She hasn't eaten anything for over 48 hours and although she'll take a little water it's not really much. The main thing is she has no energy, completely listless and just wants to sleep. How long do these things last? Is it normal for kids to sleep more or less for 2 whole days when they're ill? Son has never had anything like this.