Hi there,
Welcome to RootsChat.
Can you please give some further information about your chap, Michael CROWLEY, your 2 x great grandfather.
What information is recorded on your great grandparent's Birth or Marriage or Death certificates that gives you the details about their parent Michael CROWLEY?
If it is on great grandparent's birth certificate, then was the informant Michael Crowley, or simply named as the baby's dad? Hopefully Michael was the informant, as that would be first hand information, and the information should be reliable. Does it record Michael's then age, usual address, occupation, place of birth, when and where married? Does it record similar information about the baby's Mum?
Cheers, JM