From Inside the Grey House:
As she walked calmly up the stairs, Natalia started twirling her own necklace, almost wishing she could hypnotize Vincent into giving her what she wanted. It had been nice being able to get her necklace back. She was now using her mom’s old necklace, as hers was lost in the woods. After taking her mom’s necklace out of the jewelry box, Natalia cut the string and sang the words, taking extra care to weave her will into the tiny silver beads. Lilly guessed once that the necklace and songs were probably a spell of sorts, but assured Natalia it was still all her own will at work. Her first trial with the new necklace had been on Anthony; she found she could still control him. She tried it on a rare occasion when they were alone in a room with Vincent.