Hi Sue,
He's a mystery man and a real nomad. As stated before I believe he travelled between Ireland, Douglas, Liverpool and possibly Scotland. My grandfather had a pretty good education and his parents and the other siblings could read and write. I'm only hazarding a guess that with three small children and possibly a sick wife in 1891 ( year of her death) that he wouldn't have travelled. Maybe the census was never completed by the Millers or never filed. What I do know is that his sons Henry and William show up 10 years later in Ireland in 1901 with my grandmother, again this Alexander was not at home !

Regards
Frank Millar