Do you think Severus Snape is Draco Malfoy's father? My kids think I'm nuts (naive creatures that they are ...). It's obvious that he's head-over-heels about Narcissa, and he HATES it, but I think it's been and gone and he's the dad.
Have no opinion on that point (I lost interest after book 3 -- no particular reason, just other things to read.)