Seeking info re Nels Ellestad

Nels Ellestad, then age 12 was shown by 1857 census living with elder brother Andrew (then using name Branson) in Newburg Twp., Fillmore Co., Minnesota. He was born abt 1845 at Vestre Slidre, Valdres; don't know when or how he got to America. Two other older immigrant brothers, Iver and Gulbran (Gilbert), used Gulbranson patronymic for a time, but by 1885 all three older brothers had settled on using Ellestad name; two had used Ellestad name when sailing on the brig Concordia in 1849. Don't know how or when Nels came to America; rumored to have gone to Iowa as a young man.