A prodigy is someone who exhibits some kind of skill(s) considerably earlier than most other people do.
A genius is someone who exhibits some kind of skill(s) that most other people can't do regardless of their age/training/experience.
You can be a prodigy but not a genius, a genius but not a prodigy, or both.
And if you are a genius, it might be in just a narrow area--or in several--or in many--leaving you pretty normal otherwise.
I believe Jackie is both in the area of vocal interpretation of Classical Crossover music. She seems quite intelligent in other areas, but hasn't demonstrated actual genius elsewhere. She strikes me as a genius in this specific area because I think she does what she does better than any adult I've heard--not in every single aspect of CC singing, but overall.
Seems like a lot of singers who are also quite intelligent develop several areas, as did, for example, Linda Ronstadt (pop/rock, light opera, Mexican traditional) and Renee Fleming (opera, jazzy pop).
So here's a question--if Jackie goes that way and develops a second area besides CC, what do you suppose it will be?