I Had To Leave Work Yesterday As My Daughters School

I had to leave work yesterday as my daughters school called to say she was vomiting. When I arrived she had filled 4 bags of saliva type vomit and there was a huge amnount on the floor. She continued vomiting and sleeping when we got home. The contents was just phlegm and saliva. No food. What would have been the cause of this?? Is she lacking something? She slept right through the night with no issues. This morning she was right as rain with no further symptoms.