My brother Martin has copies of both Holgates' birth certificates and both death certificates too. We have a copy of their marriage certificate as well. We have traced his voyage out to Aus etc. but have not solved the mystery of who his parents were. I have been in contact with Dad's relatives in Aus but they can only tell us about Eva's family (have you got a copy of the booklet they produced? They did all the work on that side for us!).
Yes I think we did meet once as children but I met your parents on several occasions.
By the way only Ethel was born in Aus and Doris was born on the voyage back. Clare was born on their return to Yorkshire.