Allāh does not accept to appoint to it (the Imāmate) two brothers after al-Hasan and al-Husayn (p.b.u.t.).
‘Can the Imāmate (go) to a paternal or maternal uncle?’’ He said: ‘‘No!’’ Then I said: ‘‘Or to a brother?’’ He said: ‘‘No!’’ I said: ‘‘Then to whom?’’ He said: ‘‘To my son.’’ – In those days he did not have a son.

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