There are very few records about this man or his family. He arrived with his wife Louisa and three children on the ship Köln out of Bremerhaven, landing in New York on July 2, 1881. The spelling is ‘Rietesel’, the family members are not in the Wittgenstein records, nor were they traveling with other recognizable Wittgenstein names. The highest probability is that they came from Pomerania, the only other known source of Rietesel emigrants.
The baby Robert appears to have died in Chicago very soon afterwards. I have found no other trace of this family except for daughter Auguste who is recorded in the 1920 and 1930 Censuses in Chicago as a lodger.