Family oral history maintains that his early education was made possible by his much older brother-in-law, Paul Muruthi, who insisted that young Mwai should go to school instead of spending his days grazing his father's sheep and cattle and baby-sitting his little nephews and nieces for his older sister.
Influenced by the veterans of the First and Second World Wars in his native village, Kibaki considered becoming a soldier in his final year in Mang'u.