Next video coming up tomorrow or the day after, looking at the siege of Gurganj. Jochi, Chagatai and Ogedai, three of Chinggis Khan's sons, took command of Mongol forces at this battle.
Here's a quote from Juzjani on Jochi. In comparison, here is how Juzjani describes Chagatai: "Chagatay, the accursed, was the second son of the Chinggis Khan, the Mongol. He was a tyrannical man, cruel, sanguinary, and an evil-doer; and among the Mongol rulers there was not one who was a greater enemy of the Muslims," and "Chagatay used constantly to urge Ogedai that it was necessary to massacre all Muslims and not let any of them remain."
Juzjani also says that Jochi planned to ally with the Khwarezm-Shah against Chinggis Khan, and when Chagatai learned of this, he urged Chinggis to poison Jochi. So I don't think Juzjani is making this rumour up, but heard it at some point and came to view Jochi more favourably than Chinggis' other sons, and Chinggis himself. Though he still notes when Jochi orders a massacre, such as at Gurganj.
Link to Juzjani (Raverty translation) Vol. II: https://archive.org/stream/in.ernet.dli.2015.211407?ui=embed#page/n5/mode/2up
