I found a video series about two women, autistic savants, who were arguably Dick Clark's best fans - they met him twice, and he contacted them annually on their birthday. It was really touching.
I'm linking the 3rd of the 6 video series, where they start talking about Dick Clark and their fandom, but there is more in the 4th through 6th videos, and background in the 1st and 2nd:
The rainman twins (part 3-6) - YouTube