Looking for Aikman and Smirl of Missouri and Illinois

My Great Grandparents are William Aikman and Eliza Smirl of the Belleville Illinois region and they had about 17 children I am trying to locate records of all these children and any other information on this family. My Grandfather was Theodore Aikman born Belleville Ill and ended up In Iowa he said he was Eliza 17th child and Williams 21st so William would have had a marriage prior to Eliza Smirl any help will be appreciated.