Why are those kids so powerful?

[Knight_Teutonic]

Guys, girls and non-binaries, I have a question about the storyline (not sure if this' the right place to post in, move the thread if it's not), but Anna, Charlotte and Noel until a short while ago were stuck in an orphanage, had all of their pokemon confiscated (how did they catch or train them I don't know) and were not allowed the doctor to go out, as they were considered, by the Doctor's own words, "volatile" subjects. So with so many limitations how they were supposed to be strong gym leaders and have so many powerful trained pokémon (Without mentioning Laura, member of the E4, which was just released after turning 18)?

P.S. Sorry if I'm missing out any details, but I've always wondered about that.

[Tacos]

I'd assume they haven't been there for too long. Plus, remember that Shade had an influence in at least Anna and Noel's lives so that could be one possibility.

[Wolfox]

Well you got that, and Stone evo's are a think aswell, they could just be gifts from their parrents aswell.(I know about it Radomus, I figured it out right after the gym battle)

[NickCrash]

You never know where Shade is. He might as well be EV training their pokemon.