Krieger, Kreiger, Kruger, Krueger southwest Michigan

I have a genealogy mystery/mess.I am researching The Till family from southwest Michigan (Berrien county)and have half siblings with the last name of Kruger / Krueger / Krieger/ Kreiger. The spellings have varied. Justina (Gruening) Krueger Till had the following children with her union to Ludwig Krueger. Friedrich Krueger b. 10-11-1863, Julianne Krueger b. 8-26-1865, Rudolph Krueger b. 9-15-1867. They were born in Volhynia (now the Ukraine) and are considered "Germans form Russia". They arrived in Baroda (Berrien county) Michigan around 1892.It seems that Julianne married a John Kreiger so her married name was the same or similar to her maiden name. Possible children from that union Rhinehold(wife Bertha?), Augusta, Edward, Walter, Elsie(maried a Radde?). Brother Rudolph may have changed the spelling of his last name from Krueger to Krieger - he married one Bertha Nitz in 1898 in St. Joseph, Michigan.I would like to hear from anyone with info on this line. Thank you.