Lynette is King's wife and King Junior/Howard's mother. We don't see a whole lot of her, but what we do see is pretty sad, since she and King have an abusive relationship. In our first introduction to her, when she is diapering her child in the car while King screams at her, she bears visible signs of abuse from a recent beating (and is just seconds away from another):
Lynette's face, stained and swollen, bloomed over the wheel. She was a dirty blond, with little patches of hair that were bleached and torn. (1.2.58)
In short, she's not exactly the picture of happiness or health.