She'll replace outgoing Councillor Ken Smollen, who made the decision to step down earlier this month.
A new councillor has been co-opted to the local authority in Offaly.
Sandy Feehan-Smollen will replace her husband, Independent rep Ken Smollen, who made the decision to step down earlier this month after being diagnosed with lung cancer.
She was proposed by Social Democrats Councillor Clare Claffey, which was seconded by Sean O'Brien.
Ms. Feehan-Smollen is the current chairperson of Clara Swimming Pool, and will become the second woman on Offaly County Council.
Well-wishes were paid to outgoing Councillor Smollen, who spent four years on the local authority, as his wife was co-opted.
Westmeath Man Walks Free After 20-Minute Street Brawl
"A Great Friend And Father"- Funeral Of Donal Lunny Takes Place
Ryanair Considers Temporary Staff Pay Freeze As Rising Fuel Costs Hit Profits
Irish Rural Link Wants Meaningful Action Taken Over Access To Cash Report
Offaly Man Convicted Of Sister's Rape And Assault Found Dead
Laois Housing Development Rejected By Planners
Laois Senator Demands Action On Hospital Recruitment Restrictions
Keith Barry Bringing Anniversary Tour To Athlone