Hi my great-grandma's name was agnes stermer until she married joseph seaback/seabeck.they lived in peru Il. princeton co.area.possibly even spring valley.
We called great grand ma (busha)she passed away oct.27,1971.her daughter lorraine was my grandma and she had a sister known to me as (aunt lula).
the only thing that I was able to find on joseph was possibly his father (george seaback)and his wife catherine,no dates given.
good luck on your search.