Following is from the census for McIntosh Co ND The following all immigrated from Russia in 1888
Feil, Johnb 1837 RusGerGer
Reidlinger, Peter b 1865 Rus/GerRus/GerRus/Ger (Feil) Rosinab 1865 Rus/GerRus/GerRus/Ger
Reil, Fredrichb 1868 Rus/GerRus/GerRus/Ger Rosina b 1865, and Fredrich b 1868 could be bro. and sister
Feil,John Husb1837 marr 1856 age 19 chould of had children by 1858 Christina Wife1834 (age 22) John Son1880 Henry Son1883 Samuel Son1887 Christina would be age 53, she could be step mother.If the mother died in 1887, John could have married Christina and then immigrated
Rosina and Fredrich are probably sister and brother.Since Fredrich is living with Henry (John's son) in 1930 census John could be father, cousin to Fredrich and Rosina. I don't have the Russian census yet to see the connections.