Based on the description provided, it sounds like the skin condition around your son's mouth and nose might be a fungal infection. This type of skin problem can sometimes appear as small white or red bumps resembling pimples. A suitable treatment would be an antifungal cream containing clotrimazole, which can be purchased over the counter at a pharmacy. Additionally, applying hydrocortisone cream can help reduce any associated redness. It is recommended to apply the antifungal cream twice a day for 10 to 14 days, and the cortisone cream for the same duration and frequency. Continuing to use moisturizer may also aid in speeding up the healing process. If you have any further questions, feel free to ask for assistance.