Franz Kafka's The Metamorphosis gives the events from Gregor Samsa's mind, relating his experience, surroundings, and family all from his guilt-prone point of view. Though the metamorphosis clearly refers to Gregor's transformation from human to cockroach/"monstrous vermin," a significant metamorphosis is also apparent throughout in the characters of his family - primarily his father and sister.
At the beginning of the novel, we are told (in a somewhat timidly respectful way from Gregor's point of view) that Gregor's father is a fat, lazy man that spends hours simply eating breakfast and reading the paper, depending on his son for income support. Initially not wanting to take care of the situation with Gregor, he runs away and tries cowering behind his wife.
[insert passage from beginning]
As Gregor's "condition" remains stagnant, the father realizes he must find a means of supporting his family, and decides to get a job as a banker -- taking his role so seriously, as to refuse to take off the uniform, even when sleeping.
[insert passage about father's "dedication"]
Gregor comments on his father's shockingly different appearance when he sees him a few months after his own metamorphosis. Rather than fat and old looking, he notes that his father looks stronger, younger, and sharper with his new assimilated role.
[insert]
Gregor's sister Grete starts out as a timid, young child that we only hear through the door of Gregor's room, separated from her brother as well as her parents, begging for her brother to let her in on his "dilemma." Once her brother's transformation becomes known, she immediately takes it as her role to take care of him.
[insert beginning, caring sister]
She does this quite diligently and seems the more sympathetic and caring out of Gregor's family, until the very end where she condemns him. Suddenly she has had enough of Gregor and says things that eventually cause him to give up and die.
[insert ending where she explodes]
After Gregor's death, her parents reflect on Grete's youthfulness and attractiveness, and, as Mr. Mitchell said, the essence of the ending is "Look at that fertile body, we gotta marry her off." Grete transforms from a young, essentially useless member of the Samsa family, to a hardworking and caring sister, to an irritable and fed-up adolescent throughout the course of the novel.
Gregor's father and sister transform over the course of the novel, alongside Gregor himself. Though Gregor's transformation is physical, that of his family is mental and social, and, despite the lack of a son/brother at the end, they seem better off and hopeful for the future.
*note: [inserts] above are for the potential expansion of the blog post to an essay (as passages alluded to are most likely known at the moment*