I don't know anything about Frankie's background or family, so I could be totally wrong here, but I think being in such close proximity with some decent, more mature men is doing him a lot of good.
Sure they can all have a bit of 'sexist' banter between them, but more than once he's been pulled up for overstepping the mark with regard to his comments about women, and I think he's learning that his attitude is unacceptable.
He's learning a bit about respect (for both sexes) and beginning to earn some too.
Yes, he makes me cringe sometimes, but I think he's basically a good, bright kid at heart with a wicked sense of humour and a good deal of charm.