I looked into this and found a baptismal record for a Michael Mulkerns ,Baptized on 1 sep 1855 in Galway. His parents were listed as Patt Mulkerns and Margaret Flaherty. I found a baptismal record for Patt Mulkerins 12 Oct 1838 in Galway. https://registers.nli.ie//registers/vtls000634217#page/1/mode/1up
I added a number of sources and links to Michael's biography for you to look at.
Here are a number of places you can look for potential information for Irish ancestry.