Hi Mark

If you have a subscription to Ancestry, look in the Family Trees section (input Gertrude Davis b 1854 Isle of Man) and you'll see "Cork Family Tree".

This will tell you a lot about Gertrude's family. After a quick look at it, I think that the tree owner is a descendant of one of Gertrude's sisters who married Thompson Barnes.

Gertrude's parents were Richard Davis and Ann Joughin.

Hope this helps.

Jean C