I found John Stuart Mill's life to be interesting. John's father was a radical and a prominent Benthamite. He raised his son to be the lion of their cause, and home schooled John to avoid the the state education system. John's father felt that the state schools instilled too much conformity and discouraged independent thinking.

For a time, John Stuart Mill was indeed a lion for his father's ideals. However, it should perhaps not be too terribly surprising that Stuart's independent thinking lead him to somewhat diverge from his father's perspectives.

One of the more important moments for that was in his twenties. John came to realize that even if all the reforms he wished for came to pass, he would still be unhappy. That realization lead to a nervous breakdown. He slowly recovered, reworking his father's philosophy into something that would allow him to live a life worth living.