Thanks for this.

Do you know how I could go about finding a marriage record/certificate from about 1906 for William Henry Lyall & Mary Ellen? I do not know where they married or her maiden name. She is listed as from Cork on the 1911 census, so perhaps they married in Cork?

Perhaps the marriage certificate would have his date of birth which would confirm if the "William Henry" that you have suggested are the same person.

I searched on familysearch.org and found the following...

Name: William Henry Lyall
Registration District: Cork
Event Type: MARRIAGES
Registration Quarter and Year: Jul - Sep 1906
Estimated Birth Year:
Age (at Death):
Mother's Maiden Name:
Film Number: 101261
Volume Number: 5
Page Number: 102
Digital Folder Number: 4199363
Image Number: 00099