That is very exciting!!! It's a good chance you found Caroline! I didn't see that Caroline in 1920 and 1930.
Will you please post a transcription of all records you find?
In 1910 do you mean Caroline Nelson living with Otto Nelson?
Also you found Caroline Nilsson going to Chicago, Illinois, in 1904. Please post a transcription of that record.
Please say more about Caroline's family in Sweden.