Rigathi was born to Nahashon and Mama Jane Kirigo in the year 1952 .
His loving mother passed away in the year 2019 and in his eulogy he described her as loving and caring to her children .
Gachagua has also lost two of his brothers ,Nderitu Gachagua who died on February 24,2017 .He was also the former Nyeri Governor .
Rigathi also mourns the death of his elder brother who recently died last week .The 78-year-old James Reriani Gachagua has been ailing for a long time .He was a telecommunication engineer ,kind and humble .
Mr.Gachagua attended Kabiruini Primary School gaining entry in Kianyaga High School in Kirinyaga county .
Later Mr Gachagua proceeded to Nairobi University to pursue Bachelors Degree in Political Science and Literature.
Mr.Gachagua worked as District Officer (DO) but then resigned to work as a personal assistant to the then head of public service .
He also worked as a secretary to the cabinet, Mr Philip Mbithi who served between 1992 and 1996.
Mr Gachagua is also the serving Member of Parliament of Mathira constituency .
Rugathi is also set to be Deputize DP William Ruto should he clinch Power on August 2022 elections .
Mr Gachagua is facing trial on charges of corruption and money laundering worth $65m which he has consistently denied .
Asset Recovery Agents (ARA) has accused the lawmaker in engaging in Laundering .
ARA claimed that the lawmaker posses more than 12.5 billion from three different account in Rafiki Micro Finance bank.