Good day everyone? My daughter coughed for a week with a dry cough and…

Good day everyone? My daughter coughed for a week with a dry cough and had a fever last week, we treated it for a week and went to the garden, today he has a cough again but with phlegm, expectorant, and a slight temperature..? Can you please advise on good syrups and remedies for coughing? We have tried many things, but we haven't found the most effective and safe one yet! My daughter is 2 years and 6 months old ??