The name Jerusalem, literally means foundation. Indeed, in “At Hiruharma” the farm is where the narrator’s family is founded. It’s a settlement in a rural area far away from everyone. Thus, the people who live there have to be somewhat independent. As the doctor says, by the time he arrives mostly his help isn’t needed.
Tanner, indeed, is fairly independent. He manages to get his wife through the birth almost on his own.
Another quality, however, is needed. That’s faith. What saves Tanner’s second baby is are carrier pigeons. Tanner decides to buy them on his way home from the doctor’s house. While it seems unlikely that they’ll help. Their flight brings the doctor in time to find the second baby in the afterbirth—the baby that survives to help the narrator. So it’s not just independence that saves the day.
Tanner’s odd neighbor, Brinkman, is someone who also has faith. That his oddly hardheaded optimism might be associated with faith is, perhaps, what makes him such a likeable character.