The Final Nightmare by Rodman Philbrick

I can’t imagine where it could be. Did you look in the case in my room? I thought I packed it but it’s possible I never did .
    We are retracing our steps in a desperate hope of finding the jewel. It’s the only inheritance I have from my mother and without it all our hopes for the next few years are dashed .
    If you find it please telegraph me at once .
    Take good care of little Bobby and give him a big kiss from his mom and dad .
    Affectionately,
    Sarah Wood
    A missing jewel? The witch-thing had been screaming something about a jewel that night in the attic. But what would a ruby have to do with Bobby?
    I spread out the second letter, hoping it would have some answers.
    Dear Alice,
    We’ve nearly given up hope of ever recovering the jewel. I’m afraid we’re going to be too poor to keep you on as a nanny for the next few years. But don’t worry. We’ll give you an excellent reference .
    Our last hope is that the ruby is still somewhere in the house. We’re making plans to be home by next week and I’ll turn the place upside down looking for it. I can’t believe it’s really gone!
    Tell Bobby how much we love him and miss him .
    Affectionately,
    Sarah Wood
    I looked at the date on the top of the letter. It was written just a week before Bobby died. But I didn’t see how any of this solved the mystery.
    Then it started to make sense, sort of. The jewel the witch-thing was looking for must be this same ruby Bobby’s mother had lost!
    I turned to tell Steve. He was smoothing out a sheet of crumpled newspaper.
    â€œThere’s stuff in here about Bobby,” he said, sounding excited. “All about how he died and everything.”
    I scooted over and grabbed the paper, feeling my heart quicken once again. But there wasn’t anything I didn’t already know from the papers Katie and I had found in the attic.
    The newspaper described the tragic death of little Bobby Wood. He’d fallen from the cherry tree in his backyard while his parents were in Europe. Only the nanny, Alice Everett, had been home at the time of the accident.
    â€œBut Jason,” said Steve, frowning, “how could Bobby fall from the cherry tree? When you hear him at night, doesn’t he fall from the top of the stairs?”
    â€œExactly,” I said. “The newspapers got it wrong, that’s one thing I’m sure of.”
    â€œHey, here’s more,” said Steve excitedly. “Something about a missing teddy bear and a big ruby.”
    â€œWhat?” I snatched it from him.
    â€œHey! I found it first,” Steve complained.
    â€œYeah, but it’s my ghost,” I reminded him.
    The beginning of the article told of Bobby’s death again. Then it said: “ In an odd coincidence, the child’s favorite plaything, an old teddy bear, is nowhere to be found and the same is true of the Wood family’s most prized possession, a magnificent ruby. The jewel was left to Mrs. Wood by her mother and provided the collateral for her husband’s business loan. If the ruby is not recovered it is expected Mr. Wood will lose his business. And if the teddy bear is not found, a little boy will go to his grave alone .”
    â€œThat’s creepy,” said Steve. “What’s ‘collateral’ mean?”
    Proud to know a word Steve didn’t, I dug into what I could remember of my parents’ conversations. “It means something valuable. You take the jewel to a bank and ask the bank to lend you some money. Then if you can’t pay them back the money they keep the collateral—the jewel, in this case. But since the ruby was missing, the bank must have taken Mr. Wood’s business instead.”
    Steve looked disappointed. “Oh. Well, I don’t see what all that has to do with ghosts,” he said, tossing the bits of paper back into the trunk.
    â€œNo,” I said slowly. “I don’t, either.”
    But I knew