Yes. The processing abilities that are required to make a good speller are the some of the same processing abilities that make a good reader. Beginning readers who have trouble spelling often have trouble becoming efficient readers as well. In my experience, adults who consider themselves poor spellers are often phonetic spellers. Take a look at the spelling mistakes that your son is making. Do his mistakes seem to spell out the sounds of the word? (kuk for cook, hoo for who, nite for nigh, joos for juice etc) This would indicate that he is trying to spell phonetically. If your son is making this kind of mistake, he is on the right track. He is putting the sounds of the words in order, a task some readers find very difficult. This kind of child may need a bit of support to learn the actual spelling of the words. Or does it seem that his spelling mistakes don't follow the sounds of the word at all? (sgt for sight, chrp for truck, ement for equipment, cshus for curious etc) Your son may be making one or both of these types of mistakes.