Daredevil great - grandson achieved milestone with adrenaline - fueled stunts . he jump as third skydive after taking up the hobby at sea . Supergran wanted to swim with sharks to avoid fear of sharks .
Daredevil great-grandma marked milestone with adrenaline-fueled stunts . Birthday jump as third skydive after taking up the hobby at 92 . Supergran wanted to swim with sharks to highlight perils of overfishing .