Thank you for your query on Healthcare Magic.
Is child having cough?
Is rapid breathing present in child?
It is looking like some mucus formation in the throat because of irritation by the vomitus.
Mucus will be cleared by cough and infants usually swallow the mucus.
If there is cough and difficulty in clearing phlegm you can use oral drops like ambroxol
after consulting the pediatrician
and his examination of the child.
Hope I have answered your query.