Hello, I've had a looksee for any of your folks. I see Helen's marriage in 1924 and she says she was 19.
I've found the marriage record for Lawrence, her brother
in NS Vital Stats. https://www.novascotiagenealogy.com/
He was married in 1931 in Sydney, age 23 and reports he was born in NFL, in 1908. I could not find the family in the 1901
or the 1911 Census. No further trace of them at all.