What is the significance of the Christmas rolls in the events of chapter one

The first recipe given is for Christmas rolls. The narrator warns that the onions needed to make the rolls are known to induce unstoppable crying. She curses this annoying consequence and recollects her great-aunt Tita’s similar sensitivity to onions. Apparently Tita was so sensitive to onions that she cried from within the womb whenever anybody chopped onions. Indeed, one day Tita’s crying became so violent that she induced her own premature birth and caused her mother to go into labor atop the kitchen table. When Tita emerged a flood of her own tears came out along with her and covered the entire kitchen floor.