They were four. Suddenly, they became three when King Corona took the life of Abba Kyari, the powerful chief of staff and one of the most influential advisers to President Buhari. The three are Mamman Daura, Buhari’s beloved nephew, Ismailia Isa Funtua, his in-law (Funtua’s son is married to the president’s daughter), and Babagana Kingibe,…