William Ruto has picked a man two years his senior as his 2022 running mate.
Born in 1965, the fifth born in a family of former Mau Mau freedom fighters from Hiriga village in upper tea-growing Mathira is just a first-term MP for Mathira constituency which he won in his debut in 2017.
In that race, he had edged out a bitter rival Phyllis Wambura Maranga who had claimed she had been rigged out of the Jubilee Party primaries.
The younger brother of first Nyeri Governor Nderitu Gachagua who died on February 24, 2017, was a former district officer who also worked as personal assistant to Head of Public Service Philip Mbithi in the Moi years and has been a consistently radical soldier in the side of the Deputy President.
He was seconded to the Kanu presidential candidate Uhuru Kenyatta in 2002 as a personal assistant and resigned from the public service when Uhuru lost those elections to National Rainbow Alliance (Narc) to work for the opposition leader until 2006.
Gachagua said in a past interview that he left employment under Uhuru in 2006 to concentrate on business for which he spoke glowingly about doing business with the government in the Kibaki years.
When his brother Nderitu was elected as the first Nyeri Governor in 2013, Rigathi stayed by his side, out of his government but offered advice and support where necessary.
Nderitu fell into health problems shortly after the elections, leaving him as an unofficial overseer in his constant and long absences.
Ruto's choice was among the rebel MPs who defied Jubilee party leader Uhuru Kenyatta and continued with the disguised DP's campaigns branded "Tang'atang'a by the president.
Gachagua is an excellent grassroots mobiliser who holds a Bachelor of Arts (Political Science and Literature) degree from the University of Nairobi. As a provincial administrator, he underwent paramilitary training at the Administration Police Institute and an Advanced Public Administration Course at the Kenya School of Government.
He is facing a graft case and the Ethics and Anti-Corruption Commission (EACC) has applied to freeze some of his bank accounts.
In an interview early in the year, he called this a sad chapter coming from a man - Uhuru - that he served loyally, and described it as a small hiccup - "the flu that would soon be on the way."
Despite the bitter fallout, he vowed that his secrets with Uhuru were safe, describing himself as an 'officer and a gentleman".
He is married to Dr Pastor Dorcas Wanjiku Rigathi, with whom he has two children.