First, the good news for Castle fans: the show has been renewed by ABC for a third season.
Now, the semi-spoileriffic news: viewers will eventually meet Rick's father. Just not any time soon.
Asked when this might occur, creator Andrew W. Marlowe told TV Guide:
"That's a fun, delicious mystery and not one we're looking to solve anytime soon. When we touched upon it this year, one of the things we learned is that Castle is fine having it as a mystery, so he's not seeking it out. But I think if we're on long enough, we'll have the opportunity to explore it."
Based on recent ratings for the series, there's a good chance this will happen.