Children were born...
Children were born, they grew up, and they died, hearing these curses and never knowing the truth. In A.D. 750, the Abbasis seized the caliphate, and they exterminated the Umayyads. But they were no less rabid in their animosity to the family of Muhammad Mustafa than were the Umayyads. In fact, some of them outdid the Umayyads in persecuting his children and their supporters.
The one characteristic that both dynasties shared, was their built-in animosity to the family and the children of Muhammad Mustafa. Edward Gibbon The persecutors of Mohammed usurped the inheritance of his children; and the champions of idolatry became the supreme heads of his religion and empire. (The Decline and Fall of the Roman Empire) Robert Payne ...Again and again we shall find Muhammadans mercilessly destroying the living descendants of Muhammad. (p. 84-85).
For 350 years, the descendants of Abu Sufyan and those who claimed descent from Abbas had made war on the descendants of Muhammad's flesh. (p. 193) Throughout all the centuries of Islam, a strange fate had hovered over the descendants of Muhammad. It was as though that part of the world which eagerly accepted the Messenger of God, had turned forever against his living descendants. (p.
Many of the books of history and Hadith are saddled forever with "facts" or "hadith" (= a statement of the Prophet) which were planted in them. History, it has been rightly said, is the propaganda of the victorious party.
The victorious parties, in the history of Islam, were, first the Umayyads and then the Abbasis which succeeded, in the words of Gibbon, in "usurping the inheritance of the children of Mohammed." Once they had the instruments of power in their hands, they were free to write or to manipulate the history of the early days of Islam as they liked.