ACNP practice population

[acnpohio]

Hoping someone can help me out. I am certified as an ACNP through ANCC. I took boards prior to the AGACNP. What is my practice population? Our program advisor always said age 13 and older, however I can't seem to find a clear cut definition on the ANCC website or through the state board of nursing. I have a job opportunity at a dermatology clinic that treats peds, but am uncertain if I am able to take this job with my certification. I will obtain my Dermatology NP certification after a fellowship/residency with the group I would be working for. Would this enable me to treat pediatrics within the scope of dermatology? HELP!!!! So confused