Who is Rex Gascoigne from Daniel Deronda and what is their importance?

Rex Gascoigne is Gwendolyn's cousin. He first meets Gwendolyn while home from school and quickly falls in love with her. Certain that she will return his affection, he is devastated when this turns out to be untrue and remains in bed for several days. When he is again up and around, he tells his father that he wants to go to America to start a new life, but his father convinces him to wait before making that move. Rex heeds his father's advice, and he later becomes a lawyer.