Poor thing! M. heart breaks to hear M. little ones cough - especially now that doctors don't recommend drugs!
I've used honey three ways. First is a 1/2 to 1 teaspoon directly in to the mouth right before bed. It coats the throat to calm the cough enough to get to sleep. I would do another in the night when the cough woke M. boy up.
Second - M. son loves this - I call it 'honey tea'. 2 teaspoons of honey into 4-6 ounces of warm water. Again, it would sooth the throat and calm the coughing. We did this multiple times a day. I'm a big tea drinker and M. son thought he was a big boy by sharing teas with mom. :-)
The third is a part of another 'brewed' tea. It is a cough and cold remedy, tasty if you like stir fry. 1/2 fresh lemon (cut in half), 1 inch grated fresh ginger, 1 clove of crushed garlic in simmered for 20 minutes in a saucepan in a cup to a cup and a 1/2 of water. Squeeze the lemon juice out (it's hot!) and strain all ingredients. To serve, add honey to make it palatable. Drink warm. This recipe is also used for the prevention of colds as well as making colds go away quicker.
I found the last recipe on the internet and it's worked for everyone in M. family. Look up homemade cold remedies. There are a LOT out there.
Hope this helps and the cough goes away!