Squall/laguna[maybe a spoiler thread]

[Cloudane]

I don't think either of them knew. As far as I remember, Squall was handed over to the orphanage and Laguna wasn't told (knowing those snobby Winhill residents, they probably deliberately kept quiet about his son just to spite him.) Squall didn't know even know who his mother was, as he was too young to remember, and he never met Laguna until the Dream World. Laguna might've known after "Ellone told him everything" but probably didn't want to distract Squall with such a sensitive issue until the mission was over (he might've flipped out)

Also I don't remember any evidence in the game (though there might've been) that Laguna had a chance to actually marry Raine before she died, only that he proposed. That could be another explanation for Squall's surname.