James--I hope this helps.I would question a son being born in Canada and then a later one in Dublin, but I suppose they could have returned.
Here is the information on my James Frith--he was born 1809 in Surrey, London and married Mary Ann Minifie 1 Jan 1834, Isleworth, London. Mary Ann was christened 12 Jul 1814 Saint Martin, Westminister, London.Their children (I have since found another) were all born in London--at different parishes--MaryAnn 1837, James John 1837, William Henry 1839, Caroline 1843, George 1844, Edward 1849, Frederick 1851.
I have letters from some of them etc. and would be happy to give you more information if this should turn out to be your family.I do not know James's parents.