I just looked through old messages, and thought I would search for your names in the 1865 census for Norway. I found Ragnhild or Ragnhilde Monsdatter, 12 years old at Henriksbø farm in Eivindvik parish, Sogn og Fjordane. Her father is Mons Hanssen, 44 years old, and her mother is Dorthea Siren Schelderup Ottersdatter, 35 years old.
They have four other children as well. Olai (16), Hans (4), Barbara Petrine (15) and Brithe (9).
It seems like there are a lot of houses on the farm, and that Mons has several brothers living in the other houses. Dortheas mother seems to be living here as well. Her name is Pitrine Dorthea Schelderup Johannesen, 65 years old.
There are no Hans with the right age living at Kjellevold farm in 1865, but there are eight boys named Hans aged between 22-26 years old living in Eivindvik parish at the time. One of them is living in Nordgulen school district witch is within Eivindvik as well. I would guess that one of theese boys is the right one, and that he is eather born at Kjellevold, or that he and his family moved there after he got married. Theese young men all have their lastnames after their fathers firstnames. I would guess that your Hans changed that into using the name of the farm and the place he came from as familyname instead.
I hope this was new to you. I can check it out some more later.