If my son asked me what Sonic was, I would tell him that he is a video game character who is very fast and can run on water. I would also mention that Joe Rogan is a big fan of Sonic and has even made him his personal mascot.
1. Ask him where he heard it from
2. Tell him its from a video game his parents never played
3. Watch as my son miraculously pulls the ability and wherewithal to cope and seethe straight from a hat
4. Autism diagnosis