a climber has set his sights on the summit of k2 - the second highest mountain in the world - 20 years .
her son tom ballard , one of the world 's most accomplished climbers , plans to conquer k2 himself .
the climber was just six years old when his mother died while descending k2 , which is regarded as more difficult to reach than the summit of mount everest , that 's how i 've gone on .
' last month mr ballard became the first to solo climb all six of the great north faces of the alps in the winter season - and now he is training for k2 that