Many years ago one of our therapists suggested that we take pictures of different block set-ups for Mr. T to copy to help him learn the basic constructions for playing with blocks (tunnel, road, bridge, mountain, etc.). So we did that and tried to work with him on these building set-ups every once in a while over the years. We never really got much interest from him and I don't recall him ever actually initiating playing with these cards or the set-ups they depicted.
And then, the other day we looked over into the living room and saw this:
You can see he's already built a mountain set-up and he's working on a tunnel. On the ground you can see the card he's using as his guide.
Here he is showing me the card with the tunnel on it and his own tunnel. I was so amazed that he finally, finally initiated this on his own and actually used the cards I'd made so long ago!