In such a situation where your child has had a cold for over a week and has a wet cough, it is recommended to use a specific technique to help clear her nose and reduce the amount of mucus in her throat. Using a syringe without a needle and saline water, you can help alleviate the cough. Administer 5 mL of saline water in each nostril, 5 times a day for at least 3-5 days. If after 5 days the symptoms persist or if she develops a fever, it is advisable to consult a doctor.