I just wrote a long but not very helpful reply - then lost it.
I just can't figure out what Colson/Colston has to do with Norway. Of the 50 or so Vilhelm etc. (first or middle name) born Kristiania/Christiania 1855-1865, quite a few are foster children. A couple have mothers named Pedersdatter or fathers named some variant of William, but not enough to go on.
Occupation? Catholic? Middle name? Anything like naturalization papers or death certificate/obit or whatever corresponds to 'social security'? Married in Norway?
Afraid I'll have to give up on this one without more info. Sorry. Hope someone else steps in with good ideas.