Constant coughing in my sons

Dear Doctors,

My two sons came down with a very nasty cough. They are ages 3 and 4. It is a wet sounding barking type of cough. I tried giving them Nux Vomica 30C, Phosphorus 30C, and Hepar S 30 C and Pulstilla 30C but nothing worked.

They also have a runny nose. It has been day three. As soon as the morning hits, they start the coughing. At night they cough a little but generally are okay. But the coughing is constant and loud coming deep from the chest. I think it is a infection. They haven't run any fevers except a little slight fever tonight.

Both of their cheeks are red and the 3 year old had some bleeding from his right nostril today. They breath pretty heavily at night and their noses are stuffed up but during the day it is watery clear.

They haven't spit any mucous although yesterday one of them coughed so much that he vomitted a little and there was a long thick white spit coming out.

Any remedy you can give me will be good. I think they
got sick b/c of the very cold weather we have been having.