I have an ancestor called Thomas Cashin, so I looked at your e-m and then at my records. Do you have details of the 1881 Census? because I do and have Joseph and M living at 33 Patrick Street in Peel with a Thomas Cowley and his wife, I presume, Margaret.
There is also an Elizabeth C (Margaret's sister?), Joseph Cashin, aged 1 and Thomas E. aged 5m!
Joseph was aged 27 amd Marg. 24.
There must be some connection, I should think between your Cashins and mine as my Thomas also lived in Peel. His daughter, Kezia,was my grt. g. mother and I hope to find out more about them when I visit the I of M at the end of the month.

If you'd like any more info', please feel free to write to me directly as I don't have much time this week to browse the Bulletin Boards! Regards, Jo