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In page Đurađ Branković:

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Despot Stefan had appropriated for himself properties that were part of the hereditary lands of Vuk, which resulted in Vuk joining the opposition.[1] Vuk entered a pact with the Ottomans when Stefan had left Ottoman service and joined Hungary, fueling the domestic conflict between the two cousins; Vuk befriended Musa, only for revenge.[1] The conflict went on for 10 years.[1] Once reconciled, Stefan tried to make the most benefit of Đurađ, Vuk's son. Being childless, despot Stefan Lazarević made Đurađ his heir.[1] When Đurađ succeeded Stefan, he was mature with rich experience, aged 50 in 1427.[1]