"It's funny," Cas said. "I always thought that'd be Lily and James." She shrugged. "Maybe I'm just an old-fashioned romantic. Too many Muggle films too early, you know?"
"As for children, I agree. I can't see her without them. Or, at least without something or someone to nurture. She's got the little Kneazle, but even they only need so much love. Eventually, I'll guess she'll have great-grandkids, or kids of her own. Either way, I doubt she'll leave her nurturing to stew."
Cas tried to imagine Snape, as she remembered him, as a father. Maybe it was the age she had known him at, or maybe it was knowing more of him than actually knowing him, but the image simply wouldn't come. Then again, she tried picturing James as a father, trying from about the same age as she pictured Snape, and found herself no more capable of conjuring any sort of paternal image; everyone knew had that had worked out, though. She decided it had to do something with teenaged boys as reference points.