A 2-inch lesion is indeed the linear variety, not the one with systemic complications, which i don't think you need to worry about at all. The ones with complications are large and on many areas, unlike your son's. You can leave the lesion alone. When your son gets older, he can opt to have it cut out if it bothers him, though most people don't bother.
Not to worry.
Dr. Rockoff
Dr. Rockoff