I don't have a current Ancestry subscription so was unable to contact my cousin that way. I don't want to pay for one at the moment because I have one on Find My Past.
I have a partial family tree drawn up in the 1980s by Constance Radcliffe, which shows John Thomas Morrison born 1871. The tree does not include all available details because I suspect that my uncle, who commissioned it, made it pretty clear that he wanted it to show that all earlier generations of the family were thoroughly respectable, ie. no children born within weeks of a marriage. This would be because he had been thoroughly shaken by some 'digging' I had already done. I have since filled in some of the details previously missing, which my uncle would definitely not have wanted to know (!), but have not found a definite baptism for John Thomas. The family always lived in Maughold. At least, they are there in every census, but I wouldn't be surprised to find this baptism elsewhere on the island. In 1911, John Thomas Morrison is a mariner living in Ramsey and puts himself down as born in Maughold.
My downloaded documents are on another machine so I cannot give further detail at the minute. Still hoping my cousin sees this ! Thanks.