go to Manx museum (they will be very helpful) + look in index for births of your gfa - age 55 at death thus born c.1908 - that should give you his parents (or you could pop into general registry, spend about £6 and buy a birth cert) - once you have his parents then you should be into censuses - work back from 1901 - all these are in Manx Museum along with indices - once you get back the baptisms are available within the filmed parish regs