My 6 week old grand daughter strains and grunts constantly and vomits after having a feeding she has a hernia on her belly button is pushed out?

Vomiting 6 weeks old: It's common for babies to vomit often in the early weeks as they adjust to feeding and as their bodies develop. Blood or bile (a green substance) in the vomit , or persistent forceful vomiting , in a newborn within half an hour of eating or weight loss or dehydration requires immediate medical attention. Umbilical hernia is commen in newborns, but have to be checked by a pediatrician.