or you can desatureate the picture and then use the history brush over the part you want colored. this wont work unless you have not cropped or rotated the picture.
This photo is very interesting. I like the expression on her face. "Precious Moments" is right. How did you get the color and black and white mixed so well? Is this in Photoshop, or...? Also, I checked out your homepage -- pretty cool, but very small print :-)
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