Ghost town, mountains, mentally challenged boy, juvenile fiction

A mentally challenged boy lived with his father and older sister. He couldn't seem to please his father so he spent a lot of time back in the mountains. He found a ghost town and decided to start repairing it.

I remembered more last night. The boy's name was Jeremy. I believe he befriended an older man while he was working at the ghost town. Now that I think about it, he may have only repaired the church in the old town. After he was finished he invited his father and some other people to a celebration at the church.

A poster at another forum found this for me. The Everlasting Hills by Irene Hunt.