PC Penhale's older brother, Sam, is in town. From the get-go it's obvious that Port Wenn's lone police officer idolizes his brother thinking Sam's the hero while he's the zero. Then the Doc started noticing Sam has symptoms of a neurologic condition that could be genetic, PC Penhale went into a hypochondric overdrive.
Speaking of hypochondria, Mr. Routledge had been pestering the Doc with boy-who-cried-wolf medical complaints to get him to be referred to a nursing home. Louisa gets involved and it looks like Mr. Routledge will get his wish after all.
Louisa is also getting paranoid about her pregnancy, first believing the baby has not moved, and then, prompted by Dr. Montgomery's "findings" thinking that there's something wrong with the baby because it was small for its age. On both incidents the Doc reassures her that their baby was progressing along normally.
Last among the paranoids, because of Burt's meddling, Al thinks Pauline is breaking up with him because he was clingy, boring, unromantic and he follows her around like a lamb.
The moral of the episode, each one of them had it in themselves all this time but they were too busy looking outside for validation. PC Penhale proved to be the better person than his crook of a brother. Al had more "nice bits" that Pauline loves than the little irritating quirks she complains about. Louisa had Martin's assurance that their baby was healthy all along.
On a side note, I think Dr. Montgomery is steadily making herself a third party in the Louisa-Martin romance. She's actively pursuing the Doc and coming down hard on Louisa. But Louisa has an edge - the Doc is definitely falling in love with their baby.
