Born Greenock, resided Old Kilpatrick, enlisted Paisley. Colin and a brother Joseph, were born in Greenock. Their names don't appear to be on any memorial

From the Scottish Military Research Forum

"My grandmother lost 4 brothers in WW1 
Matthew Sinclair HLI died 1914 
Henry Sinclair Cameronians died 1916 
Colin Sinclair Argyll and Sutherland died 1916 
Joseph Sinclair HLI died 1916"