What moral growth does huck demonstrate in his behavior at the wilkses' home?

Chapters 26-30 mark Huck's first moments of maturity. Up until this point, he followed the authority of those around him, such as Pap, the Widow, Miss Watson, Judge Thatcher, and the King and Duke. The moment Huck decides to steal the money, he breaks free of this authority. For the first time, Huck acts on his convictions and morals to help other people, rather than simply acting on his personal desires.

Huck's interaction with Mary Jane also highlights an emerging aspect of his growth, namely an interest in women. In The Adventures of Tom Sawyer, Huck viewed girls as nothing more than an annoyance and did not believe they were to be taken seriously. Here, in contrast, Huck calls Mary Jane beautiful, and comments that when he saw her light a candle in the window, his "heart swelled up sudden, like to burst."

In addition, it is notable that Huck is desperate to escape the King and the Duke by the end of the Wilks ordeal. Huck is not simply scared of them (when he first meets them he compares them to his Pap), but is truly attempting to break free from the authority and control that they hold over him.

Huck feels badly about the Wilks family being conned by the KIng and Duke. Huck is especially fond of Mary Jane the eldest sister. He sees her compasion for the family's slaves and has his own moral catharsis. He decides he will not let the King and Duke hurt these nice people.