Lady Muriel Gibbs (nee Dunn) was born in Maryborough in 1919. She was educated at the Maryborough Girls’ Grammar School and the University of Queensland, where she was a member of the Womens’ College. She graduated with a Bachelor of Arts in 1941 and a Bachelor of Laws in 1942.

She was articled to Mr Nicol Robinson of the firm of Nicol Robinson and Fox, and was admitted as a solicitor in February 1944. After her admission she was employed in the firm of Morton and Morton Solicitors, but ceased to practise after her marriage to Harry Talbot Gibbs on 17 November 1944.

Lady Gibbs lives with her husband in Sydney. They have three daughters and one son.