How sound is this hadith, and what does it mean: "The child, until he reaches puberty, whatever good deeds he does are written for his father or his mother, and whatever bad deeds he does are not written against him nor against his parents. When he reaches puberty, Allah makes the pen flow for him, and He commands the two angels with him to record and to be diligent. When he reaches forty years in Islam, Allah protects him from three afflictions: madness, leprosy, and vitiligo. When he reaches fifty, Allah lightens his reckoning. When he reaches sixty, Allah grants him repentance to Him as He loves. When he reaches seventy, the inhabitants of the heavens love him. When he reaches eighty, Allah records his good deeds and overlooks his bad deeds. When he reaches ninety, Allah forgives him his past and future sins, and grants him intercession for his household, and he becomes Allah's captive on His earth. When he reaches the most decrepit age: 'so that he may not know, after knowledge, anything,' Allah records for him the like of what he used to do of good in his prime, and if he commits a bad deed, it is not written against him"?

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