Family traits and other problems in Book 2 of Little Dorrit

Still trying to get my mind around the complexities of Dickens's Little Dorrit, as the cast of characters continues to grow well into the 2nd Book (1,000+ ibook pp.); he never tires of introducing new characters and playing with their quirks of language and personality, for ex., only this deep into the novel do we learn anything about the character of Mrs. Gowan, whose son has married Pet Meagles. She visits the Meagles family and manages to insult them all with her presuppositions that her son has married down. This visit -and her utter pretensions to wealth (she rides a hired coach, much like taking a cab or an uber today, but pretends that it's her own vehicle - equivalent to a chauffeured limo today). This episode leads up to presume that horrible people like the pretentious artist Gowan come from horrible parents - yet that isn't so, or not always, as we have throughout the counterexample of the protagonist, Arthur Clennam, himself - whose mother is a nasty matriarch. And what about Mr. and Mrs. Meagles, treated in a lightly comical manner, with their emphasis on being "practical" people, with Mr. M's obvious deference Mrs. M, and with the abundant love for favorite daughter, Pet? Well, how could they have accepted and encouraged her marriage to Gowan? And, more important, how could they be so rude and oblivious regarding their adopted daughter, Tattycorum (sp?), who rightly runs away from home? Deep into Book 2 and about 2/3 through the novel, Tatty's character begins to emerge - as we see her under the sway of the stern (but probably emancipated and a forerunner of contemporary feminism and women's rights?) Miss Wade and with some as yet unexplained connection to family that Arthur almost married into (the comically talkative widow whose name I can't remember - I'm just overwhelmed by the # of characters, sorry). In an odd and not quite believable stretch, Arthur follows her, unnoticed, through the streets of London and overhears much of her conversation w/ Miss Wade and with the Frenchman, Blondois?, who has hovered on the perimeter of this narrative - with some dark secret about at least one of the characters - since the first chapter.