When I first read this posting, I didn't see a connection.
However, with more research on my part, I now see a possibility. You made referance to Michael having 2 Brothers (Thomas & James). Would that be Sr or Jr. If it is Sr. (Michael born in 1825), then My James could be the Brother?
In 1856, Malarkey's were only located in Co. Derry (Londonderry), in all of Ireland. (3 Families). Check out my Posting of "James & Mary Malarkey". Let me know what you think?