A pediatrician is a doctor who specializes in the regular care of children, as well as the diagnosis and treatment of illness in children. Young patients are often more complicated to treat because they are still growing and developing.
While pediatricians may sub-specialize in specific therapy areas like oncology, surgery, ophthalmology, and anesthesiology, in general, pediatricians provide services like vaccinations, health exams, and treatment of common ailments and injuries. In addition, pediatricians are trained to handle the complex emotional and behavioral issues faced by children, especially during puberty.
Pediatricians normally see their patients from birth until the age of 18, although some may agree to treat patients into their early 20s, if requested.

A dermatologist is a doctor who has extensive training and knowledge of the skin, scalp, hair and nails and treats conditions that affect those areas. These doctors will evaluate any abnormality, blemish or lesion on the skin in order to determine the cause and will determine a course of treatment.
Dermatologists provide patients with full body scans in order to identify any signs that are indicative of an illness that requires treatment, such as skin cancer. These specialists may also provide cosmetic services, such as mole removal, scar diminishing treatments and even botox and face lifts.

A dermatopathologist is an expert in both dermatology and pathology. They specialize in diseases related to the skin, but where a dermatologist would examine a potentially-cancerous mole by looking at it, a dermatopathologist would examine your skin cells in a lab, more like a pathologist.
Beyond just skin cancer, dermatopathologists also study a wide range of skin conditions, including everything from warts, moles, spider veins and herpes, to dermatitis, rashes, vitiligo and other conditions related to skin discoloration.