Educated at Methodist Ladies' College, Burwood, and Ravenswood School for Girls, Gordon, she trained in occupational therapy as a teenager.

[5] Sonia Hopkins worked as an occupational therapist until 1965 when she married William (better known as Billy) McMahon, an aspiring politician in Sir Robert Menzies' government.

[6] Later that year, Sonia McMahon made world headlines after being photographed at the White House wearing a revealing dress in the company of her husband and United States president Richard Nixon.

As a prime ministerial spouse from March 1971 to December 1972, Sonia McMahon organised for a nanny to look after the children at the family home in the Sydney suburb of Bellevue Hill, while she lived with her husband at The Lodge, Canberra, attending official duties.

[citation needed] On 22 February 2009, McMahon was seriously injured after slipping on the stairs of a luxury pleasure boat owned by her friend, Paul Ramsay.

[8] While in hospital, Lady McMahon had been preparing for an appearance at the Golden Slipper horse racing event at Rosehill Gardens Racecourse on 2 April.

[10] Media outlets noted her work in contributing to the community by attending fundraisers for charity and different organisations including being on the board of the Sydney Children's Hospital as well as for her complete loyalty to her husband.