Muhammad Hijab shows his stupidity by trying to disprove the existence of the 12th Imam (May Allah Hasten his reappearance) by using the book of Al-Ghaybah which is a whole book dedicated to proving the existence of the 12th Imam!

It even has a whole chapter found on p.274 titled: 'Refutation of those who believe that Imam Askari did not have a son'
Scan has been included at the end of the video