Hi Olwen,
Thank you for getting in touch. My connection with the Gill family is that my late grandmother ( Edith May Gill ) was a sister to Daniel Douglas Gill and therefore an aunt to your late father, Charles Douglas Gill.
Daniel Douglas and Veronica Isabella had 4 children that I know of through my research, Joyce, Mildred, Brenda and Charles Douglas. I have Joyce's birth certificate, she was born 29th November 1921 in Isle of Man and also your late fathers, born 23rd June 1925 also in the Isle of Man. I have yet to get Mildred's and Brenda's which I believe she could have been adopted but not sure. Daniel Douglas Gill was one of 8 children.

Regards
Helen