Originally Posted by Slaterx
I know but after Revan might have somthing planned and he might have told shan not to tell anyone
That doesn't even make sense. What would Revan have planned? And if he did have something planned, why would he tell Bastila if he thought that it was going to harm her or their child? From the way things look, Revan and Anakin are similar, Anakin would do anything (hence his fall to the Darkside) to save Padmé and his children... Revan would do anything to protect Bastila (well except for that time in the interrogation chamber, if the player wanted to be a jerk) and more than likely their child/children.
As for your possibilities there are only a few, since canon states Revan never returned from the Unknown Regions (it's possible he was frozen in carbonite as a Sith Lord again... though that remains speculation). So it would seem that Revan would have had to have knocked Shan up either DURING
the Jedi Civil War or IMMEDIATELY
afterwards... and hell it's even possible that it was after Revan went to the Unknown Regions... Shan never once mentioned her child during TSL and you'd think that cutscene with Carth would say something about it... so it could be possible that Revan created a child through the Force, as Plagius (not sure I spelled his name right, but oh well) did with Anakin.