Angel Unaware: Jonathan, the hermit who finds Laura when she's in the mountains and advices her on her quest to talk to God. He's implied to be an angel, as when Laura is found and tries to show him to Pa and Mr. Edwards, he disappears without a trace, but at the same time can't be an Imaginary Friend, as he made Laura a cross with her name in it which fell on the water and that's how Charles found her.
Be Careful What You Wish For: Laura, when she not only prays for her brother to go away, just for a little while ... but fails to pray for his health to be restored when he gets sick. At least this is so in her own mind.
Early-Installment Weirdness: The haughty, rude side of Mrs. Olesen is depicted here, as this was the norm for her character during most of the first season. Her place as a comic foil wouldn't come until late in the first season.
I Wished You Were Dead: Laura, incredibly jealous about her new baby brother and afraid he'll replace her in her Pa's heart, refuses to pray for little Charles Ingalls when he becomes ill. And then he does …
Infant Sibling Jealousy: Laura gets filled with jealousy of her baby brother, seeing him as replacing her in her father's heart as the son he always wanted. She goes as far as to refuse to pray for his health, only to get stricken with guilt when he dies.
The Mountains of Illinois and Television Geography: The episode was conceived as a Tearjerker, but earned its place in Narm history by pundits who instead focus on the fact that Laura was somehow able to find a mountain in southern Minnesota, hoping to get "closer to God" and ask Him to exchange her for her beloved baby brother.
My God, What Have I Done?: What Laura feels upon learning that little Charles has died of his illness.
Picnic Episode: The afternoon before Laura runs away, the Ingalls family enjoys a Sunday picnic. Laura is having so much fun … too much fun.
Recycled Plot: The plot point of Laura climbing a mountain to ask God for a miracle was taken from a 1965 episode of Michael Landon's previous series Bonanza, titled "All Ye His Saints".
Series Continuity Error: Although the church bell was made and installed two episodes prior (in "The Voice of Tinker Jones"), it's noticeably absent here, indicating this two-part episode was likely filmed first, despite airing later.
Title Drop: When they learn that baby Charles is terminally ill and death is imminent, a fraught-with-emotion Charles and Caroline stay with their son and recite the 23rd Psalm, the "Shepherd's Psalm" as it is popularly referred to. The baby dies shortly thereafter.
Narm history by pundits who instead focus on the fact that Laura was somehow able to find a mountain in southern Minnesota, hoping to get "closer to God" and ask Him to exchange her for her beloved baby brother.