Interestingly according to the book, Dark Secrets of the Kenyan Presidency authored by controversial independent blogger Chris Kumekucha, the former minister did not sleep in the same room as his wives.
Koinange is said to have revealed to a friend that he was afraid of sharing a room with any of his four wives just to guard the secrets of the Jomo Kenyatta administration.
“What would happen if I dreamt in my sleep and started divulging Jomo’s secrets? I certainly cannot live with such an eventuality, so I decided never to share a bedroom with anyone, my wives included,” he once divulged.
During the late Mzee Jomo Kenyatta’s administration, Mbiyu is said to have been one of the most powerful government officials trusted with all the good and dark secrets of the president.
According to former Butere Member of Parliament Martin Shikuku as documented in other files, there was some information purely trusted with Koinange and Kenyatta could not even mention a word of it to his wife Mama Ngina Kenyatta.
“I was told to mind my business because there were things Kenyatta talked about with Koinange that he couldn’t share even with First Lady Mama Ngina,” Shikuku said.