Paul Whitehill says he became involved in the planning of Art, Autism and Remembrance — an outdoor music festival and silent auction scheduled for Thursday — for personal reasons. That is until he met an 11-year-old named Quincy Graves, who is autistic. “He tied it all together for me,” said Whitehill, head of Joplin-based Whitehill Enterprises, a private consulting firm for public art and custom tile murals.