If I am correct in that Digit Span assesses short-term memory, well...he's probably inherited that from me. My short-term recall is not great. My observation of him though, is that he doesn't have a deficit in this regard, though he may not be especially adept in this area at this time, or if ever. What I have noticed though, is that his long term memory is impressive, and that he is also able to recall minute and/or esoteric details.
Digit Span does measure short-term memory, or more exactly, working memory - how many digits can you hold in your mind at once. This is a factor in IQ because it affects whether you can keep track of everything that is happening at once in a complicated problem.
It sounds like you are doing everything right in parenting him.
Good luck - it can be a wild ride with these kids!
