Hi can you explain your question?

Drink only hot water. Take 2or 3 cloves (lavanga) keep it into your mouth.. suck that extract. Do it when you cough. Do it same at night also.
Gargle salt water. It helps to reduce cough.

During cold and cough babies can't eat properly. Give dry ginger powder in milk help for both cold and cough. Give hot water only.
Give food what ever she likes. Avoid oily foods and citrus fruits it increase the cough.
It is from more than 3days give medicine.
And consult doctor.

Gargle many times with a hot water ( no too hot ) with turmeric & salt or crystal salt added to it .crystal or rock salt is more better for this than ordinary salt .Drink slightly hot water .Avoid cold water.Eat 3 or 4 times 1 spoon crushed sugar candy with crushed 2 or 3 pepper. Drink boiled water with tulsi , crushed garlic, pepper & ginger before going to sleep in night & in day time also drink one or two times ( add sugar or jaggery ).Hope all these helps u.If dry cough severe consult doctor & cover ur mouth by mask or cloth before coughing to avoid spreading to others in house specially to kids..U can also have crushed ginger with honey once or twice .

Babies immunity will be less compared to adults ...
And till 5 years the situation will go...

Give him immunity booster foods like root vegetables,citrus fruits,green leafy,dry fruits powder,eggs...

And don't make him to play with water because babies likes to play ...

And also don't make him to go with infected people...

You can also Google as mylittlemoppet or gkfooddiary,it has few recipes for immunity boosting in kids...

And once check with the Paediatrician too...

For stuffy nose u can use baby nose spray or baby nose drops.Also u can do home remedies like slightly roasting 4 or 5 garlic in ghee or oil & making child smell the roasted garlics .It will help in opening blocked nose.Carefully do it baby should not touch the hot vessel .Same u can do & tie roasted garlic in a cloth & make a potli & keep it near his nose or on his chest for sometime while sleeping .If he is totally uncomfortable consult doctor bcoz stuffy nose leads to chest congestion sometimes .

U can try moms Co baby soothing solution lotion for relief of rashes pimples boils ND itching sensation it's natural essences soothes the skin ND heals quick leaving the skin soft ND rashes free skin

If u r breastfeeding mother then don't have too cold food, , curd or drink anything directly from fridge....drink normal room temp. Water......bcoz of ur intake baby can suffer with cold n cough.... Baby is too small so don't self medicate.... It's better to consult paediatric they will prescribe medicine for cold cough....and according to baby's weight dosage will be prescribed....

Because of air circulation. Don't sleep them directly under fan or AC. Don't use mosquito repellent for long time ,it may cause cough.
Once check this.
And he continuously coughing means consult doctor.

Give them nasal saline drops in both nostrils...... And As ur both kids have cold so better to keep distance between them... Give warm milk add little turmeric n give before sleep at night time.... And if cold cough stays after 4-5 days then consult doctor.....