How long after toddler has the stomach flu does it take to get back to theirselves?
Is she breastfeeding or is it cow's milk? Some of the stomach viruses cause an intolerance to dairy that lasts for 6-8 weeks. Breastfeeding is perfect but I'd eliminate all cow's milk (and cheese and yogurt, etc).
If its her first bout of the stomach virus you can expect to see on-going issues (stomach pain on and off, tiredness, cramping diarrhea, and even occasional vomiting) for about 10 days to 2 weeks. The first bout is pretty nasty.