Looks like you uploaded it just a tad too big and the forum compressed it, making it slightly soft.

As for the rest of the image, you clipped his hand just a tad, but not a big deal (some people will not like it). I like the composition, nice placement of the flame and your brother.

The twig has movement, which bothers me more than anything. You need to up the ISO in order to get the speed faster. I think the ISO on the T3i is 3200, so I wouldn't push it more than 2000 or so, because the noise would be too much.

Fire is very tough to shoot. It is nothing but a white blob because the exposure is set to his face. Flames do have detail if exposed correctly.