Hi Karl, I was not pointing you to the descendants of Michael Shanley, but rather to his parents and siblings which is the info you asked about.
This Michael Shanley is not part of my family tree so I actually have no info to share. From experience I had a quick look into freebmd.org and found this info which may or may not connect to your partners family tree.
A Michael Shanley married Sarah Fairish in 1912 - registered in Lanchester which is near Newcastle- so these may be your Michael's parents.
Between 1912 and 1927 they had 6 children one of whom is named Michael- his siblings??
The freebmd.org site is easy to use and if this is the right family you could go on to find out who they married, their descendants etc.
regards, Anne