Rufus Weylin doesn't intentionally set out to be like his father. When he is a young boy and falls and breaks his leg, Tom's first comment is that the accident is going to cost him a lot of money. Rufus doesn't gravitate toward Tom's rough and violent personality, but it is important to remember the setting the two men live in. In this era, they were behaving as society expected them to do. Even Dana, African American herself, notes this about Tom in Chapter 4:

His father wasn't the monster he could have been with the power he held over his slaves. He wasn't a monster at all. Just an ordinary man who sometimes did the monstrous things his society said were legal and proper. But I had seen no particular fairness in him. He did as he pleased. If you told him he wasn't being fair, he would whip you for talking back.

Rufus grows up being trained in how to eventually run a plantation and own slaves. His father teaches him how to be successful in the "family business," despicable though this is by any standards. But in this time and place, Rufus doesn't question following in his father's footsteps.

It can even be argued that by the end, he grows into a worse man than his father, as evidenced by his treatment of Alice and his manipulative treatment of their children, resulting in her suicide.

Although Rufus likely never made a conscious decision as a child to be like his father, the setting creates circumstances where Rufus becomes a little more like Tom with each passing day.