I've just copied this from Brian Lawson's Burial Index:

BIFFI, Carlo Zepperino 55 Dsg 21 Dec 1844
BIFFI, Eleanor Rus 18 Feb 1814
BIFFI, Frances 43 Dsg 13 May 1833

Have you tried searching in the 1851 census for the son? The IGI has him as Zepharine William Biffi born 1844, christened 1845 at St Georges, Douglas.