It is a figure of speech. Obviously they hadn't actually been on the verge of cutting each other's throats, it's a fancy way of saying they were all very angry and couldn't stand each other. The author's purpose was to imply that before something happened, they were very angry and unable to stand each other.
Answer:
young people these day can't reply their following one career for the whole of their working lives
Answer: They became poor immigrants due to a chain of unfortunate events. The first one to befall upon them was the murder of Esperanza's father by bandits, which flung Esperanza's life upside down. Without her father to support her family, Esperanza's uncle and Papa's brother, Tio Luis, offered to marry her mother in attempt to seize their family's riches and property. After much indecision and uncertainty, Mama decided that it was best for her, Esperanza, Miguel, Alfonso, and Hortensia to move to California for the time being. It was there that the group became poor migrants, so unlike their wealth in el Rancho de las Rosas, and worked day and night for little pay and terrible conditions.
