Who is Richard McAdams from The Favored Child and what is their importance?

Richard grows up in the household of the woman he calls "mother-aunt" with the girl he believes is his cousin, Julia. His father, John, is away in India, trying to save enough money to restore the estate Wideacre. Richard and Julia are to be joint heirs to that estate. When Julia goes away to Bath and becomes engaged, Richard is angry as he now will inherit only half the estate. Richard doesn't seem to want Julia for herself but wants her share of Wideacre. He catches her alone one day and rapes her. Then, he intercepts Julia's betrothed and sends him away. When Julia discovers that she's pregnant, she and Richard sneak away and are married, only then discovering that they are brother and sister.