In the 1930 Federal Census, Waukegan, Lake, ILL
Anderson, Andrew, b. abt 1853 in Sweden, age 77, widower, immigrated 1895
Anderson, Anna, b. abt. 1874 in Sweden, age 56, daughter-in-law, widow,
immig. 1896
Anderson, Richard, b. abt 1908 in ILL, age 22, son, sales clerk/grocery store
Anderson, Arthur, b. abt 1908, age 22, son, chauffeur/grocery store
Anderson, Margaret, b. abt. 1913, daughter, attending school
This family spoke English and Swedish, could read and write, and Andrew and Anna were naturalized citizens.
Could this be your Anders Gustav Anderson, born May 3, 1857? It is not unusual for the census to be "off" a few years on year of birth. It is also possible that Richard and Arthru (twins) and Margaret were sons and daughter of Anna and grandchildren of Andrew??? Since Margaret was only 17, I would think she would more likely be Anna's child. Andrew would have been 60 when she was born.
I did not find your Richard Petrus Anderson in this census, but have not looked in the 1910 and 1920 ones. If this Andrew immigrated in 1895, I could also check the 1900 census.
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