Cold and cough on and off since birth is not uncommon especially if the child acquired the same during 1-3 months of life.
Possibly it could be an allergic condition.
Next Steps
1. Avoid contact (other children having cold/cough/fever as this could precipitate or worsen
2. Identify any allergens the child is allergic to (eg: hay,dust,pollen,paints,silk or synthetic clothing)
3. Montelukast with a combination of levocetrizine will be beneficial
Health Tips
Medicines to be started after consulting your paediatrician