It's my pleasure to be able to help! And I'm thrilled to say I've found what happened to Sylvia. I went to the Trail directories and found the following:
1936
SEAMAN Vernon of Trail Taxi
1937:
SEAMAN Mrs Sylvia ladrs Crystal Lady r 1951 Columbia
1938, 1939, 1940, 1941, 1942 and 1943:
SEAMAN, Mrs Sylvia 1951 Columbia
1944 - she's no longer there so I went forward a few years and looked for her sons and found:
1953:
SEAMAN, Robt bottler Palm Dairies r 424 Olivia Crescent
SEAMAN Vernon D bottler United Dairies r 424 Olivia Crescent
WILEY Harold H (Sylvia) of Riverside Tire Service h 424 Olivia Crescent
now I went and looked at the 1944 directory again and found:
WILEY, Harold H (Sylvia) of Riverside Mtrs r 1959 Columbia
Then I looked at Voter Registration and found:
1963:
at 1475 Daisy Street, Trail
WILEY Harold Henry, garageman
WILEY Mrs Sylvia --
HOMER David, lead burner (this was the year after his wife Sylvia Ilott Homer died)
1972:
at 1475 Daisy Street, Trail
WILEY Harold Henry, retired
WILEY Mrs Sylvia, retired
HOMER David, retired
Another find was a border crossing in 1944 by automobile:
Harold H Wiley driving to Hanford, Washington accompanied by Mr and Mrs A M Tod and Sylvia Seaman. The address given was 1959 Columbia, Trail, BC and they were going to Lorin Mercer (Sylvia's brother-in-law - husband of Elizabether Homer).
http://search.ancestry.com/cgi-bin/sse.dll?indiv=try&db=...I then went back to Mountain View Cemetery in Trail and on the Robert "Bob" Seaman died 1 June 1997 and interred 19 Mary 1999 there is a note that says "shares the row with Harold Wiley".
I also found (not all the grave sites have been transcribed so information is missing):
Mrs Sylvia Wiley in section 60, plot 508, died 13 March 2010 and interred 21 May 2011
and
In Loving Memory Harold Wiley 1909-1982 - it has a note that says "shares the row with Robert Seaman"
So I'd say Vernon Seaman McKenzie left Sylvia and the boys in 1936/37 (maybe Robert had been born but maybe she was pregnant with him when Verne left. Vernon Jr was only 3). Harold and Sylvia married in 1944 and they may have courted for years. He'd been previously married but don't know if he was widowed or divorced. He obviously took on the role of the boys' dad. He was from Franklin, Manitoba.
I'm now searching for obits but no luck so far.
Cheers,
Soosi