Union Workhouse Glenamaddy

My great grandmother Ellen(AKA Nellie) was born in the workhouse in 1876,  Her father was a widower named James Pettit.  Her mother was Honora(AKA Mary) Rush.  They had four children and all lived at the Workhouse.  James passes away 1877; Mary passes in 1885.  The three younger siblings came to Ameria in 1888.  Where can i do more research for  details why they were in the Workhouse, where they came from in Glenamaddy, if there was more family still in Glenamaddy.

Thanks for any help you can provide.

John Martin Degen 

jdegen1@san.rr.com