Once there was a boy named Tom, and he lived with his mother and father in a little house in the big city, but every summer he went to the country to stay with his grandmother for one week. That was Tom’s favorite week of the year. He loved his grandmother’s house. She had a big backyard, with a garden and a tire swing hanging from a pine tree in the corner. She had a dusty old attic with only one tiny window, which let in just enough light for exploring the piles of old furniture and boxes of treasures without ever being bright enough to take away the mystery. Best of all, she had a whole room filled with books where Tom could sit for hours and read about all the places in the world he would visit one day.

At his grandmother’s house, Tom ran free from attic to cellar, but there was one door he was never allowed to open. Upstairs, just across from the little room where he slept, that one white door was always closed. Tom knew that it was locked tight because he had tried to open it many times. When he asked his grandmother about it, she always said, “Some things are not for children.” That was a very annoying answer, but since it almost always came with homemade cookies after, Tom didn’t hold it against her.

Things continued in this comfortable way until the summer that Tom was ten. That year, he went to his grandmother’s as usual, and ate a huge dinner the first night as usual, and slept in his own small room as usual. The next morning when he woke up, though, the little white door across from his was open just a crack, which was not at all usual. Tom knew that his grandmother must have left it open by mistake, but this was exactly the sort of mistake he had been waiting for all his life.

His curiosity burned as bright as ever, and he tiptoed across the hall and lay his hand on the handle of that door. His heart was pounding as he slowly pushed it open, and in that instant, all the possibilities of what could be inside, things he had imagined over the years, flashed across his mind. Maybe there was a chest full of treasure, left there by a pirate out of gratitude to Tom’s grandmother for saving his life one stormy night. Maybe he had a crazy aunt, locked away all these years because she thought blue was red and talked endlessly about the sky falling. A mummy? Stolen art collection? Dracula sleeping in his coffin? Proof of the existence of Bigfoot? A shiver whispered up his spine, but Tom told himself not to be silly. He stepped into the room.

It was completely ordinary. A wide, comfortable-looking bed filled most of the room, with tiny tables painted white sitting on each side. One rocking chair sat in the opposite corner, but no crazy aunt was rocking in it. A bright rag rug was on the floor, and the walls were painted light green and completely devoid of famous art. Tom felt empty inside. He had been so sure that something wonderful was in here. He looked under the bed. Nothing but dust bunnies. Why had he been kept out if this was all there was? He turned toward the closet door. This was his last hope. This time when he opened the door, he held his breath, but all that greeted him was a neatly hanging row of clothes, and some old men’s shoes lined up on the floor. No secret chests of treasure, no wonderful maps, no mummies in the far corner. Utterly disappointed, Tom closed the closet and walked over to the wide window. It looked out onto the back yard. The sun was shining, and the huge apple tree was covered with white blossoms. Tom felt very old. A childhood dream had been lost. Here he was in the secret room, and the world looked way more interesting outside.

Tom wasn’t as old as he felt, though, and like all children, he couldn’t linger in a gloomy mood for long. Not when the smell of bacon and pancakes was drifting up the stairs. Not when all that sunshine outside was calling to him. He ran down and ate his breakfast, saying nothing to his grandmother about the room. Instead he ate in silence and planned his morning. He rather thought that apple tree would be perfect for building a tree fort.

After breakfast, Tom sped outside, eager to get started. He knew where his grandmother had a pile of old boards out by the shed. He would use those for his fort. When he rounded the corner into the backyard, though, he stopped and looked around, confused. Where was the apple tree? His grandmothers garden was in the corner, just as he had seen it from the window. The sun was shining down. The fence was newly painted white. But there was no apple tree in the yard at all. He remembered climbing that tree when he was younger. He tried to remember whether it had been there the year before but found that he wasn’t sure. Quietly, he went back inside.

“Grandma, what happened to the apple tree in the back yard?”

“Remember that, do you?” She sighed. “It was struck by lightening two winters ago and had to be taken down. Such a pity. That tree produced dozens of pies every year. But don’t you worry. I’ve got cherries, so pie is still on the horizon.”

When she turned back to her dishes, Tom slipped quietly back upstairs. He crept into the unmysterious mysterious room. There, out the big window, the branches of the apple tree waved lightly in the breeze. Tom didn’t feel like playing outside any more. He spent the rest of the day reading instead, but even in a book he couldn’t escape the persistent questions that wandered around the back of his brain. That night, he had a hard time falling asleep, but eventually it began to rain, and the sound of the raindrops pattering on the roof relaxed him at last.

The rain was still falling when he woke up the next morning. The first thing Tom noticed when he left the room was that the little white door was open even wider than before. Unable to resist, Tom crept inside the room. Then he stopped short and a shiver went over his whole body. Outside the wide window, the sun was shining brightly on the blossoms of the beautiful apple tree and a lovely breeze skipped through the flowers in his grandmother’s garden. Tom could still hear the rain on the roof. He ran back to his own room and looked out the window. It was gray outside, and a steady stream of rain fell, puddling up all over the front the yard. He slowly walked back across the hall, drawn irresistibly to that impossible window. He wondered if it opened, and if so, what he would find when he stuck his head outside. He looked for the latch.

“That window never did open.”

Tom’s grandmother was standing in the doorway behind him, and the sound of her voice made him jump so high, he hit his head on the window ledge.

His grandmother didn’t seem to notice. She just slowly came into the room and sat on the bed. “So now you’ve seen my window.”

Tom nodded slowly and sat down in the rocking chair. He wanted to ask a million questions but none of them came to mind. The two of them sat in silence for a while. Then his grandmother began to talk.

“When your grandfather asked me to marry him, he told me he would build me the best house I’d ever seen, and he did just that. He built this place with his own hands, and when it was finished, we got married and lived here all the years of his life. Your father was born here. Your mother brought you here when you were only a week old, and your grandfather held you on his lap in the library downstairs and read you your first book. The next spring, your grandfather died. It was completely unexpected. He was out in his workshop as usual, and his heart just stopped.

“After that, your father suggested I move into the city with you all, but I couldn’t do that. This house is a part of your grandfather, his personality fills it up from attic to cellar. As long as I’m here, I feel him every day. I did close up this room, though. This used to be our bedroom, and I couldn’t face coming in here, so I locked the door and left everything just as it was. For a long time, I felt that the day your grandfather’s heart stopped was the day mine stopped, too. I spent too much time just sitting on the porch swing and staring at nothing. My garden was grown over with weeds. The books that your grandfather loved were covered with dust.

“Then your mother brought you for a visit. You were one year old. She set you on my lap and handed me the same book that your grandfather had read to you. I started to read, and you listened to carefully, it was like you were grown up and not a little toddler who just wanted to run all over the house. Every page of that book reminded me of your grandfather, and getting through it all was the hardest thing I’d done yet. But there you were looking up at me and waiting patiently for the end of the story. When it was done, I set you down and you began to explore, but I just sat there thinking. It was like I could hear your grandfather saying, ‘Get up. Get on with it.’ So I did.

“That night, I opened this door. This room sat here just as it always had. And there, out the window, was the sunny afternoon in spring, everything exactly the way it was on the afternoon your grandfather died. It should have been dark outside, but in here, it was bright daylight. I sat in that chair where you are and watched the birds flying back and forth and felt happy for the first time in a year. That was when I knew. Life goes on. I had you and your father and your mother and my friends and my garden. A life. But I would also have this. Forever. So I locked this door and I went downstairs and I made you your first apple pie. But after that, whenever I needed to talk things over with your grandfather, I came in here and he was waiting for me. And even on the darkest days, the sun was shining out that window.”

She fell silent after that, and Tom sat there, looking at the window. He knew now that the door had not been left unlocked by mistake. He knew that he was old enough that his grandmother wanted him in here. That by sharing with him her favorite place on earth, she was introducing him to her favorite person. Suddenly the window didn’t seem creepy at all. So he held his grandmother’s hand and rocked in the chair his grandfather had made and looked out at the sun shining down on their past.