Katherine Beckett and Richard Castle. Opposites attract. It had been nineteen years since Rick had proposed to Kate. Since then, they had four children together: a son, a daughter and twin boys. (the timelines don't exactly match up 100%. Had I made them match up, Kate would be in her fifties and Rick his sixties and I didn't want that. I wanted them to be just about as they are (age wise) on the tv show) **DISCLAIMER** I do not own any of the rights to ABC's Castle, or any of its characters.