Add 1/4 to 1/2 of package of reactivated dry yeast to the bottling bucket before bottling. Then that yeast will eat the corn sugar I assume you will also be adding at bottling and will carbonate the bottles.
if you added the yeast to the carboys now, I don't think much will happen because the initial yeast most likely ate most of the sugar. If anything, you would get a small secondary fermentation, but it would not carbonate the beer.
Member of the Metro South Homebrew League (Mash-Holes) - Weymouth, MA
Primary - Hall & Oats Stout
Secondary - Amber Waves of Grain Ale
Kegged - Patriot Porter, Bourbon Barrel Aged Patriot Porter
Bottled - Winter Warmer Stout