Gunborg Hancock was born in Helsinki, Uusimaa, in what was then part of the Russian Empire. She was the youngest of three daughters born to parents Georg Westling (1879–1930) and Elin Lundblad (1875–1953).

She married George Londen, who would die just a few years later in the Winter War. In 1943, three years after the death of her first husband, she married Robert Hancock. After the German invasion of Finland in 1944, she and her husband fled to Sweden aboard a passenger ship, where they would live with another family for some time. They later moved to Paris, France, where she worked as a typographer. After divorcing her husband in 1958, she returned to Stockholm, where she resides today.

She has been the oldest living person in Sweden since the death of 112 year old Flarid Lagerlund on 9 April 2022. A few months later, on 18 July 2022, she became the oldest living person in the Nordic countries following the death of Finland’s Astrid Qvist.