fanfic research

[Magnus9]

Well I am planning on starting a Usagi fanfic sometime in the near future. I already have the timeline of the story pretty much set and since I've been reading UY since I was 8 or 9, thanks to my library card, I pretty much have the characters down except for one thing that I either can't remember ever being clarified in the comic or it never was.
Does Kenich know that Jotaro is not his son?

As far as I can see it he does. I believe I read somewhere he married Mariko while she was carrying Jotaro. So he should know. Also it would explain the extra resentment Usagi that he sensed during the Homecoming story arc. I couldn't find or think of any story that clarified it. It's especially hard sometimes when I'm attending school in Arizona and many of the comics and books I collected while growing up are in a storage box at home in Hawaii. Any help would be much appreciated.

[Stan Sakai]

Does Kenich know that Jotaro is not his son?

Yes, Kenichi does know that Jotaro is not his son.