I found a family history website with 3 Frederick Angers living in the Niagara Frontier during the War of 1812:
http://dorothystewart.net/genealogy/anger-family-tree/

None of these three men appear to match the information in the 1851 Census for Grey Co. but do appear to be the men who served in the 2nd York and Lincoln Militias during the war. This raises the question of when your Frederick Anger came to Upper Canada and who his parents were as he did not match their birth dates or was not born in the US or Canada.