Born in Nyeri County, Kihara built her career in administration and the private sector before joining elective politics. Her entry into Parliament followed a by-election held after her husband's death created a vacancy in the Naivasha parliamentary seat.

Kihara attended Riamukurue Primary School from 1961 to 1968 before joining Githunguri Girls Secondary School, where she studied from 1969 to 1972. She later attended Cathedral Secretarial College and obtained Pitman Examination Institute certificates in 1972 and 1973, according to her parliamentary profile.

Her professional career began in 1976 when she joined the Ministry of Labour as a shorthand typist. In 1979, she moved to Gailey and Roberts Limited, where she worked as a personal assistant to the sales manager until 1981. She later joined Philip Morris Services Incorporated, serving as a personal assistant to the general manager from 1981 to 1985.

In 1986, Kihara joined Orbit Chemical Industries Limited, where she held positions including transport manager and credit controller. She remained in the private sector until she entered Parliament in 2003.

Kihara won the Naivasha parliamentary seat in a by-election in 2003. During her first term, which lasted until 2007, she also served as an assistant minister. However, she lost the seat in the 2007 General Election.

In 2013, Kihara contested the Naivasha Senate seat but did not win. She returned to the National Assembly in the 2017 General Election, securing the constituency seat on a Jubilee Party ticket. During the 2017–2022 parliamentary term, she served on the Departmental Committee on Lands and the Committee on National Cohesion and Equal Opportunity.

In the 2022 General Election, Kihara won another term on a United Democratic Alliance (UDA) ticket. According to the election figures provided in her profile, she received 44,882 votes. Her victories in 2003, 2017 and 2022 represent three successful parliamentary elections.

Her parliamentary voting record includes decisions on taxation and other major legislative issues. Records published by Mzalendo indicate that Kihara opposed a proposed 35 per cent top income tax band during a vote on June 20, 2023. On June 22, 2023, she voted in favour of the Finance Bill 2023 at the second-reading stage.

In June 2024, Kihara voted in favour of the Finance Bill 2024 at the second-reading stage and during consideration of the committee report, according to her published voting record. The bill became a major subject of national debate over taxation, government revenue and the cost of living.

On October 8, 2024, Kihara voted against the motion to impeach former Deputy President Rigathi Gachagua. Her vote was recorded during the parliamentary proceedings concerning the proposed removal of the former deputy president.

Questions about Kihara's political alliances and future plans should be distinguished from her documented parliamentary history. Any claim about her current party affiliation or plans to contest the next General Election under a particular party should be verified through an official announcement or a reliable, up-to-date record.

Kihara's political career has included electoral setbacks and returns to Parliament. After losing her seat in 2007 and failing to win the Naivasha Senate seat in 2013, she returned to the National Assembly in 2017 and secured another victory in 2022.

Her record includes parliamentary representation, assistant ministerial service, committee assignments and votes on major legislative proposals. Her next political chapter will depend on whether she seeks another term and the outcome of the next General Election.