Myko Olivier, Molly Quinn and Nathan Fillion Myko Olivier, Molly Quinn and Nathan Fillion

Rick Castle (Nathan Fillion) faces an emotional milestone on the Oct. 28 episode of ABC's Castle when his daughter, Alexis (Molly Quinn), moves out of his loft and into her own apartment — with her boyfriend, Pi (Myko Olivier). "Castle does not respond well at all," says Quinn. "He's angry about it because he knows how [he himself has treated] women, but he's not the kind of parent who can say no."

With Alexis and Pi sharing a futon, the implication is that little Alexis — gasp! — has lost her virginity. Quinn refuses to let her mind go there. "I'm still pretending that's not the case, but it is the reality," she says. "I've heard that a romantic scene may be coming up."

Castle's nest won't be empty for long. An episode set to air around Christmas will find Castle and Beckett (Stana Katic) taking in the orphaned baby of a murder victim. "It will be interesting to see Beckett and Castle exploring how they would parent a child," says Katic. "It's going to be so sweet!"

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