Michael Collins b. September 1822

I have a big family mystery on my hands.  My grandfather's Collins line ("the Humphreys") was out of Lissane.  Granddad's (1895 - 1988)  father was Humphrey Mickey Collins (1858 - 1910), whose father went by Mick or Micky (1822 - 1901).  I am trying to understand the origins of my gg-grandfather Mick.

Since he named his oldest son Humphrey, I've assumed that Micky's father's was also a Humphrey.  There was indeed a Humphrey Collins in Lissane, married to a Johanna Barnane early 1820.  They had a daughter Catherine in late 1820, followed by their second child John 1824.  The problem is, there is no record for a child named Michael in that 3+ year gap or before or after. 

There WAS a Michael Collins born to a Humphrey Collins and Ellen Sweeny (Sept 1822), only the residence was given as Blue Hill (Knockgorm), and there are no other children for this couple and there is no marriage record.  The godparents on the record are practically unreadable but I think they are Brian McSwain (Sweeny?) and Margaret Shea. 

There WAS a marriage record for an Ellen Sweeney to a Denis Collins in Blue Hill, and they went on to have several children, including a Michael in 1838.  So that's a different couple. 

Micky's father Humphrey may have married a Mary Galvin (O'Brien) and had several more children who show up in the Skibbereen RC records.  It looks like Johanna Barnane was alive, recorded as a godmother as late as the mid 1840's so Johanna Barnane's husband Humphrey was not widowed at that time.

My gg-grandfather Micky married Ellen Driscoll in February 1854.  Around the same time, one Catherine Sweeney married a Laurence Hourihane in neighboring Tooreen.  I mention this because a Catherine Sweeney showed up as a witness to the wedding of Micky to Ellen Driscoll.  Is it the same Catherine Sweeney and was she a relative of Mick Collins?  One of Mick = Ellen Driscoll's children had a Mary O'Brien as a godmother - maybe Mick's step mother?

Anyway, I've reached an insurmountable brick wall here - how did Mick born 1822 in Blue Hill end up in Lissane and what was his father Humphrey's relationship to the other Humphrey in Lissane who was married to Johanna Barnane?   Was Mick related to Catherine Sweeney, the wife of Laurence Hourihane?   It seems like only a terribly inquisitive mind from the Lissane area would know something about this.  If anybody in the area knows any of this scuttlebutt, I'd love to hear more!