Looking for info on Devans, Roycroft, Seberry Family Lines

Kate Devans was born in Ireland about 1818 and eventually married Edward Roycroft, born in Ireland about 1825. They lived in Sligo eventually. I haven't been able to find birth information on either of them, or thier parents names. In 1866 their son Charles Roycroft born about 1846 married Eliza[beth] Seberry born about 1841 and I believe the marriage took place in Cloonclare, Manorhamilton which seems to be where the Seberry family lived. Eliza was the daughter of Henry Seberry and Anne. We dont know her last name but there has been speculation it could have been "Feathers. " Any information helping me trace further back would be so very appreciated!

I am at a total roadblock here, but am feeling passionate about unearthing my family's Irish past.  We have Charles & Eliza moving to Scotland (they are on the Scotland 1881 census) and having most of their children there, eventually coming to the US. Charles arrived  in Sept 1886 and was naturalized in 1889. Seems Eliza come over in 1887. So that 1901 census is perplexing, the ages of Eliza and Edward are within 5 or so years of their birth dates I have, but I don't know about a daughter names Sarah. My info shows they should have been in the US at that time. I have basically nothing on Edward Roycoft Sr. or his wife Kate Devans, so I can't get further back in my genealogy. :(

*also it seems that a daughter of Edward and Kate, who never married, named Ellen, in 1916, wrote to the government through the vicar at Ballysumahan to enquire of her age during the 1851 census. They responded that she was 2 months and living in Kinkillew. 

Any help is so very much appreciated by my entire family!