In our modern day, Kino's family members might be called "enablers", because their actions allow Kino to persist in his destructive pursuit of material riches. Juana, even in her simplicity, perceives the potential evil presented by the pearl, but when she is physically rebuffed by Kino she submits to his authority and keeps her peace. Juana plays the role of the submissive, compliant wife, and even though she knows in her heart that Kino's actions will result in their ruin, after her initial protest Juana remains silent.
Juan Tomas is Kino's brother and nearest neighbor. He and his wife Apolonia unquestioningly support Kino's decisions, and it is Tomas who accompanies Kino when he goes into town, first for the Doctor, and later to sell the pearl. Like Juana, Tomas's and Apolonia's loyalty enables Kino to persist in his misguided quest. When the family's hut is burned and they must flee the village, Apolonia's calm presence of mind assures that their survival is kept secret until they can get away, and Tomas's industry secures for them the supplies needed for their escape.