The daughter and grand-daughter of Fraserburgh residents Alistair and Adele Macdonald are raising funds for the Brain Tumour Charity.
Former Fraserburgh Academy pupil Karen Macdonald and her daughter Isla are undertaking different challenges on the same day in different countries.
At 1.30am on Saturday, June 15, in Motala, Sweden, Karen will have 24 hours to cycle 300km (186 miles). Her target time is 15-plus hours.
On the same day, at 5pm in London, Isla will be attempting to swim 150 lengths (3.75km) in a target time of two-plus hours.
If all goes according to plan, mother and daughter will complete their challenges at exactly the same time but in different locations.
Karen was moved to take part when two people very dear to her were belatedly diagnosed with brain tumours. The family’s godparent and brother-in-law Sam Ferguson, and close friend and colleague Michelle King both died from brain tumours.
Karen is a keen cyclist but has never undertaken an endurance challenge of this magnitude.
If you would like to sponsor Karen and Isla, please visit www.justgiving.com/KARENandISLA to support brain tumour research and diagnosis.