you pretty much repeated what I said.. lol...

Voices are genetic... accents are not. But usually accents are fully developed into a person by that age... unless they're trying consciously to remove it. I had a brittish accent as a child... but I was born in Florida and NO ONE has that accent in my family... I eventually lost most inklings of it... but I still have trouble saying certain words and have a preference to saying words with an english twist. Like, it's not a-dult... it's Ah-dult... I don't say gair-age though lol

It's hard to say. You could argue either way... without knowing the history of Boba, I would say that he was close to his father, and that wouldn't want to remove himself from his father by getting rid of his accent. But we could create a whole story line for why he changes it... lol