Andrew if this is the same David Kewley is my great, great, great uncle born in 1850 Douglas Isle of Man. Son of Joseph Kewley and Margaret Cain. He is credited to saving 38 people from drowning in his lifetime. He is said to have died from exposure in his last rescue. An intresting mad. If your sister can access the Isle of Man Examiner 15 jul 1955. She will find a article titled the Story of Dawsey Kewley. If you would like a copy of the article let me know. My dad George Henry Kewley has been resurching this line for about 15 years or so.