Suggest Medicine For Child Suffering From Cough

my son is 5 yrs old and my daughter is 2 yrs old. My son s weight is 15 kgs and daughter s is 13.5kgs. Both are suffering from cold and cough. Been giving them alerid syrup and servil junior. Cold is reduced mostly. Cough is persistent, mostly when weather is chill. Which cough medicine can i give them both as servil junior isn t available now anywhere?