The tidings of his son's death caused the loss of two members of Jacob's family. Bilhah and Dinah could not survive their grief. Bilhah passed away the very day whereon the report reached Jacob, and Dinah died soon after, and so he had three losses to mourn in one month.
He received the tidings of Joseph's death in the seventh month, Tishri, and on the tenth day of the month, and therefore the children of Israel are bidden to weep and afflict their souls on this day. Furthermore, on this day the sin offering of atonement shall be a kid of the goats, because the sons of Jacob transgressed with a kid, in the blood of which they dipped Joseph's coat, and thus they brought sorrow upon Jacob.