Hi Diz
Although i am away from home i was able to do a little checking.
I have Mary Jane Shimmin bpt 23 April 1845 in Castletown. At this point not sure where i got the info probably family search.
I found John and Mary's marriage on ancestry.com Liverpool Lancashire marriage and banns 1813-1921. Her father's name was listed as robert Shimmin coachman. The 1871 and 1911 census have her being born in malew / castletown. The 1911 census stated Castletown which should be accurate as it was filled out by John T. Their marriage date is e Dec 1876 in Liverpool.
Carol G