Nils Olsen Kjos from Ringsaker

In 1849, Nils Olsen Kjos, b. 18 September 1805, his wife Ingeborg, and their children Karen, Ole, Johan and Gønner, emigrated from Norway, sailing on the Flora and arriving in New York 23 August. The passenger list is on this site /emigration/passengers/?journey=606 They are numbers 5-10. The father, Nils Olsen, apparently died shortly after their arrival in New York, but I have not been able to confirm it. Does anyone know whether there are sources for such a death of an immigrant in New York? The widow Ingeborg remarried, probably shortly thereafter, to Christian Johnson. I have not been able to document when the marriage took place, or where the remaining family members went first. They turn up in Goodhue County, MN, in the 1860 census. Later Ingeborg and Christian lived in Sauk Center, Stearns County, MN. I have also been able to follow the four children, who mostly lived in Goodhue and used the names Caroline Nelson Eggleston, Ole Nelson, John Nelson and Gunda Nelson Hemmings. Nils Olsen Kjos made an exploratory trip to the US in 1846, to see whether it would be viable to move his family to America. After he returned, a publisher in Lillehammer named Prehn interviewed Nils and published a booklet with the unwieldy title, "Beskrivelse over en Rejse som Gaardbruger Niels Kjos fra Ringsager paa Hedemarken i Aaret 1846 har foretaget fra Norge til Amerika og tilbage igjen, samt hans paa denne Rejse gjorte Iagttagelser angaaende Nybyggernes Forhold og Stilling der" (Description of a trip that farmer Niels Kjos from Ringsaker in Hedmark in the year 1846 undertook from Norway to America and back again, including his observances concerning the living conditions of the settlers and their position). This pamphlet was widely read and led to the start of "mass" emigration from Veldre and Ringsaker. During his exploratory trip, Nils contracted malaria, and this may have been the cause of his death in 1849. Any clues about how to find records of immigrant deaths more or less on arrival in New York during this period would be greatly appreciated!