Hi All

We're trying to trace my half brother's biological father.
(For info, we're not trying to make contact, if anything we'd just like a name and photo for our own curiosity).
We've done a 23 and Me DNA test and found some 2nd Cousins on his biological father's side on there. One of the 2nd cousins, is related via great-grandparents, and she kindly shared her great-grandparents names.
The names of which are:
Edward Kelly 1843 – Near Louisburg
Bridget Scahill Approx 1846 – Near Louisburg
I haven't shared the other set of great grandparents names because I believe, with the other cousins matching to me on the site, listed at Kelly, that the above are the set of great-grandparents we share.
Now, another kind man, helped me find the children of the above great-grandparents:
Mary Kelly - 1881 (1911 Census)
Patrick Kelly – 1882 (1901 Census) - Moved to America (This is my 2nd cousins grandfather)
Norah Kelly - 1884 (1901 Census) Not on 1911 Census, potential emigration?
Edward Kelly Jr – 1885 (911 Census)
Does anyone know how I found out the names of who the above married / children they had?
I think that would get me very close to finding out potential name of his biological father but I will admit, I'm not a natural at this. My brain has never hurt more trying to figure out relations and what it all means. Hats off to those of you who are good at this. Columbo I am not.