both goverments had prime minister's and parliments
Yes, Canada trades with Great Britain.
Canada is still around. So is great Britain.
Originally a colony, and later a dominion.
By 'How' I guess you mean 'Who' and even so the question is an odd one as there is no prime ministerial relationship between the two countries. The PM of Britain is David Cameron and the PM of Canada is Stephen Harper.
In the beginning, Great Britain funded Canada
At this point Canada was no longer a colonony of Great Britain, therefore, Canada had no obligation to fight along side of Great Britain.
Great Britain acquired Canada as a result of the French and Indian War. During the war Britain colonized parts of Canada and then took over the rest of the country after the war.
Great Britain.
The U.S. had a close relationship with Great Britain, and the war interfered with trade.
both Great Britain and France
Or not. Canada has been at war with many Nations but never Britain, at least not directly.