I'm going a bit nuts trying to figure this out. It's one of those things where it's not really important, but I can't find something I sort of thought I knew and it's nagging at me.
Basically it's a short story I read relatively recently (Though it might have been in a really old anthology, since I pick those up now and then, or it could have been relatively new). If I recall correctly it was a modern fantasy story, about a little boy (Could have been a girl though) who has some kind of magical talent or power, but lives with a person (I think a woman, but could be a man) who he thinks is his parent, or aunt/uncle or... something? Anyway, this person forbids him from using his powers, and maybe is keeping his powers suppressed somehow as well. And it seems like they're pretty cruel to him.
It seems to me that it took place mostly in the house he lived in, it's possible he was kind of kept prisoner inside.
I know that's absurdly vague, but that's why it's driving me nuts.
The only marginally specific thing I remember is the ending, with him somehow breaking away from this parent figure and fleeing out the door into the yard... and then he's caught, I think, but I think it turns out that the person he's been living with isn't really his guardian, but someone who kidnapped him or something, and was planning to steal his power or... something.
I remember some external force shows up to save the day at the end, telling him that, and that they've been looking for him but he was hidden while he was in the house, or something.
I'm probably getting everything wrong or mixed up, but... can anyone help me out here?