What is the recommendation regarding charity equivalent to the weight of a newborn's hair?

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It is virtuous to give silver in charity equal to the weight of the newborn's hair. This is supported by the report that the Prophet, peace be upon him, instructed Fatimah upon the birth of Al-Hasan to shave his head and give silver equivalent to the weight of his hair to the poor and the Ahl al-Suffah. Ahmad narrated this. Sa'id also narrated in his Sunan that the Messenger of Allah, peace be upon him, performed the 'Aqiqah for Al-Hasan and Al-Husayn with one ram each, and he gave silver equivalent to the weight of their hair in charity. Furthermore, Fatimah used to shave the hair of any child she gave birth to and gave silver equal to its weight.