Hello..there are certain questions that needs to be answered here..Is the cough associated with fever,cold..Is she otherwise active..when is the cough more during the day/night..The vomit that you are talkjng about post cough looks like a post-tussive vomit..There are various causes of cough and the treatment differs accordingly..
Next Steps
visit your paediatric and let the doctor examine her and find out the exact cause..No point giving cough medicines without having a diagnosis in hand.
Health Tips
Dont worry as long as she is active otherwise..it would mean its either an allergic / viral cough..allergic cough would require certain medications..viral cough takes its own time to recover(only symptomatic treatment is given). So visit your paediatrician.