this seems to be a case of congestion in chest that generally aggravates in evening and morning, may be because of many reasons, like asthma, allergy of a reactive airway disease
. you should get her evaluated urgently if there is respiratory difficulty, rapid respiration or lethargy
or irritability, as if ignored, it may be bad for your child.
may be she requires nebulization with bronchodilator
for relief. vomiting
wont be helped by any anti emetic when congestion is there.
hope i am of help in guiding you
Dr. Amit Kumar