Despite not knowing whether her baby belongs to her deceased husband, Mark or Jack, Mel begins Season 4 with a sense of optimism. For years she yearned to be a mother and her dream is one step closer to reality. While Jack is supportive and excited, the question of paternity continues to gnaw at him. Complicating matters is the arrival of a handsome new doctor, who's in the market to start a family of his own. Hope is still healing from her car accident, and the lingering psychological effects of her brain injury will have profound consequences for both her and Doc. Brie, intent on proving the innocence of the man she loves, unexpectedly finds herself in a closer relationship with Mike and one step closer to Calvin's violent criminal web. Even as Preacher forges a new romantic connection, he can't help but hold out hope for being reunited with Christopher and Paige.

Mel seeks medical care, with a nervous Jack by her side. Hope's confusion puts Doc in a tough position. A new doctor joins the practice.

Jack and Brie's father causes friction when he comes into town. An incident at work affects Mel. Doc gets to know his unexpected visitor.

Mel plans a dinner for Cameron to meet Jack, but plans go awry. Connie warns Lizzie to be careful with Denny. Preacher befriends his aikido teacher.

Hope's concussive symptoms continue, frustrating both her and Doc. Meanwhile, Mel asks Preacher to help her surprise a stubborn Jack.

After Hope and friends sew the costumes, Lizzie and Ricky rehearse for the Renaissance Fair. Brie and Mike team up to investigate who paid Brady's bond.

The Renaissance Fair kicks off. Mel worries about Jack after a familiar face triggers painful memories. Denny watches Lizzie and Ricky perform.

Joey arrives with some shocking news that has Mel questioning her sister's judgment. Jack brainstorms a new revenue stream.

Mel plans a surprise for Joey but is distracted by her concern for Jack. Lizzie struggles with telling Doc what she saw in Denny's drawer.

Mel deals with the aftermath of Jack's disappearance while also getting troubling news from Stacie. Mike and Brie continue their search for Calvin.

Charmaine asks Jack for support at the baby shower. Mel has a tough conversation with Cassandra. Preacher worries about Christopher after their call.

Vernon and Hope argue about seeking in-home care, Mel confronts Cameron about his odd behavior, and Jack gets his glamping Airstream up and running.

Mel and Jack finally receive the results they've been waiting on. Lizzie organizes a send-off for Ricky before speaking to Denny about his secret.