Yusuf is the son of Hajiya Aisha Halilu, the second wife of the president-elect.
Buhari is divorced from his first wife Safinatu, with whom he had five children, and married Aisha, 44, in 1989. They also have five children together.
She is a Fulani from Adamawa state. Buhari and Aisha have only one son, Yusuf: the others are girls.