Eight-month-old babies with vomiting and diarrhea should be highly considered to be infected with rotavirus enteritis, which occurs between the ages of six months and two years and manifests itself as vomiting first, followed by diarrhea. Some babies may also have fever. If the vomiting is not frequent, you can feed your baby formula or breast milk as normal. In addition, the baby should be hydrated in small amounts to avoid dehydration. You can also take oral probiotics to regulate the intestinal flora, and you can also take oral montelukast to make the stool dry up. If the baby vomits a lot and vomits everything he eats, then it is recommended to fast first. Wait until your baby’s vomiting subsides before letting him eat.