Who is Brown from Sister, Sister and what is their importance?

Thaddeus, nicknamed Brown by his father, is Valerie and Inda's brother. He is 5'11" and in training to become a police officer. When Brown runs into Inda and Chiquita at a Los Angeles nightclub, he defends his sister when she gets into a confrontation with Raymond and Gina. Brown falls in love with Chiquita.