Hej Göran, You might get some good information from the Douglas county historical society in Alexandria, MInnesota.They have family files, death records, etc.It won't cost you too much - $20, and if they don't find anything, they probably won't charge you.Records that they have can be scanned and emailed to you.
You can use this page to contact them online.I usually am a research volunteer there in the summer months.So I think that is your best chance for Alexandria information.
If the mother died in 1883, this might be the daughter Emma, who is living in Douglas county in 1885, right name, birthplace, and age. Maybe living as a foster daughter with a family in the town of Holmes City, not far from Alexandria, and in the same county, Douglas County.
name: Emma Peterson event place: Holmes City, Douglas, Minnesota age (expanded): 7 years birth year (estimated): 1878 birthplace: Sweden race: White gender: Female family number: 61 volume: Douglas page: 8 gs film number: 000565737 Household Gender Age Birthplace Emma PetersonF 7y Sweden John EricksonM 51y Finland Annie EricksonF 54y Finland Mike EricksonM 25y Norway Carrie LondonF 34y Norway Charley EricksonM 18y Norway Thom EricksonM 15y Norway Lanna EricksonF 12y Michigan
The answer you have gotten already that referred to the Angen family, there is information at the historical society about that family. The historical society may also have information about the City Hotel. There are also old business directories - very old ones.