Lucy and Fred - what do you think about the lack of a mole? Can moles grow that big in adult hood but be entirely missing from the child?
* Some people are born with moles. Other moles appear over time.
* Sun exposure seems to play a role in the development of moles and may even play a role in the development of atypical, or dysplastic, moles.
* The role of heredity cannot be underemphasized. Many families have a type of mole known as dysplastic (atypical), which can be associated with a higher frequency of melanoma or skin cancer.
http://www.emedicinehealth.com/mole_removal/article_em.htm