In the kingdom of Granada Sultan Abu Hassan was deposed by a palace coup after he married Zuraya a.k.a. Isabel de Solís and exiled his former wife, Aïxa al-Horra. His son by Aïxa, Muhammed XII Boabdil succeeded him. Fast forward a bit and Boabdil is deposed by the same man he had deposed. Abu Hassan died in 1485 (according to wikipedia), and was succeeded by Boabdil who was the final sultan of Granada.
Now for the WI: it be unthinkable for Abu Hassan when he retakes the throne to do what happened in the Ottoman Empire and have his predecessor murdered? Or was that a strictly Ottoman thing? Likewise, did Muhammed have any FULL siblings? Can only find his half-siblings Nasir/Fernando and Saïd/Juan de Granada.
And what of Aïxa? OTL the Granadans threw Abu Hassan out because of his slight on replacing her (a descendant of Mohammed) with Zuraya? She seems unlikely to be one to let something like her son being murdered stop her - I mean, she was the one who advocated that Granada use the women, children and elderly to fight the Reconquista. She's also author of the famed quote to Boabdil "thou dost weep as a woman for what thou couldst not defend as a man!" So, I feel she'd definitely be a force to be reckoned with, son or no.