welcome to health care magic forum,
As you have mentioned that your son is having cold
problem and repeats ever 3/4 weeks, so this shows that he is suffering from recurrent cough
and cold, and there are many reasons for that.
As you have also mentioned that he is having a whit spot on his cheek and some time suffer from stomach ache and his appetite is low, so it is possible that he has worm problem too, and this can also be one reason for his recurrent cough and cold,
so it's better to go for Homeopathic
treatment where he will have complete cure for all his problems that too with out any side effects, Homeopathy
is always safe and best for kids.
For more info you can mail us at firstname.lastname@example.org or visit us at www.drkackerhomeopathy.com