The Sea Wasp (Ryk E. Spoor)

Most parents give over a portion of their lives to care for their kids--some give up even more than that for a child with special needs. But I notice you skipped over the second question, about whether you would take on her condition if it meant you could protect her for her endless life.

And if I told you that she was still your same old daughter, but with the fangs, thirst for (small amounts) of blood and aversion to sun/garlic, if I said she stopped aging and developing but didn't show any signs of being "unholy," and if I said there was no guarantee the transformation would work the same way for you... Well, you don't have enough information to act yet and you don't know what you'd do.

Which is perfectly fine.