The only story Samuel actually believed [about the origin of his grandfather's sword] was the one that his grandfather told him on his deathbed, when he bequeathed it to him. By then, Samuel had already learned the truth about the things that go bump in the night. A wraith had literally sucked out the brain of his best friend, and Samuel had narrowly managed to kill it.

But somehow, Grandpa Campbell knew all about the monsters. As he lay in his four-poster bed, staring at young Samuel as intently as he could with rheumy eyes, the cancer ravaging his stomach and sending him into frequent fits of coughing, he told him about the family claidheamh mor, and how since the 1700s, the sword had been used to kill any number of malevolent creatures.

"And now," Grandpa had said to Samuel between coughs, "I want you to slay your own monsters with it."

Mary, though, had known just how different things were from when she was eleven years old and watched her parents exorcise a vengeful spirit.

[...]

There were times when Mary wondered what it would be like to have a normal life. Most of the time she was happy not to have one, because the only way to live a normal life was to remain ignorant. Sure, she'd be able to go to birthday parties and hang around with her friends and do all the other things teenagers did, but she wouldn't have known that at any moment a vampire or a shapeshifter or some icky creature might come to kill her.

No, knowledge was power. She preferred to know what was coming. If that meant fewer dates, then that was fine.

Samuel's dry-cleaning business and Deanna's occasional substitute-teaching work provided them with enough money to pay for Mary's education and allow them to keep their armory stocked.