The Secret

When Mike and Sully stop to check on old Mrs. Johnson, they discover her dead and a young boy, Zack, hidden in the closet. Mike takes the child in and confronts the townsfolk, who reluctantly admit to knowing the boy's mother was one of Hank's whores. When she died they sent Zack to Mrs. Johnson because he was ""simple."" Mike is frustrated in her attempts to find a medical diagnosis and cure for Zack's condition. Mike's further detective work reveals that Hank is Zack's father, and she helps Hank own up to his responsibility.
Meanwhile, Brian seems to be the only one to get the boy to exhibit his artistic abilities, and he is mistakenly given credit for a drawing that Zack has done. Later, when Zack's artistic talent is discovered, Hank agrees to send him to an art school in Denver. The show has a cute opening scene of Mike and Sully with him criticizing her driving.