Preparing a will is a duty ordained (2:180). Allah decrees a will for the benefit of your children. (Since the sons have the responsibility to take care of the family, and daughters will be cared for by their husbands, or if unmarried, by other males in the family), sons get twice the share of daughters. If two, or more, daughters are the only inheritors, they get two-thirds. If only one daughter is left, she gets one-half. If the deceased has left any children, then parents get one-sixth each. If there are no children, and parents are the only heirs, the mother gets a third and the father gets two-thirds, since the male has the fiscal responsibility of the family. If the deceased has left brothers or sisters, the mother gets one-sixth and the father gets one third. Remember, this distribution shall take place after fulfilling the will if the deceased has left one, and after paying off all debts. As for your parents and your children, you know not which of them is more deserving of benefit from you. Such is the Ordinance from Allah. Verily, Allah is Omniscient, Wise.