Thank you for your suggestions. I have searched the US censuses and found some information, however it hasn't helped me really discover when they immigrated. A big problem with locating any information of their previous names is the spelling seemed to change with each document. For instance, my grandmother's maiden name is Ohodnicky on one of her children's marriage licenses and Ohotnicqy on another. On the censuses, my grandfather's age ranges from birth in 1872 to birth in 1890! I believe 1872 to be the correct birth date as he was many many years older than my grandmother who was born about 1896 and it is also the date used on his funeral mass card. I also know the 1930 census (where the 1890 bithdate is claimed) information to certainly be the correct family, as my father and uncle are listed as sons. The inconsistency in dates is crazy. Neither became citizens, they each carried green cards (I do have a copy of my grandmother's).

I will try to contact their old parish in Michigan and see if there is any information they can share from my father's birth certificate. Thank you for that tip, I totally skipped that step!

Thanks again for your wonderful help, it has given me many more ideas to forge ahead on!
Linda