The movie star admits he has to "audition" for young movie fans - and even then they're not convinced he is who their parents say he is.
He explains, "They don't get it... I'm like 'Ka-Chow!' and then the kid's like, 'Yeah, yeah, he's doing like Lightning McQueen does'. They never really get it. It's odd.
"We had the premiere for Cars 2 and a family brings their kid over: 'He's such a big Lightning McQueen fan, can we get a picture...?' The kid starts to cry... he's afraid of leaving his parents and I'm left kind of like I don't know what I'm doing.
"Then the dad had to come into the picture and then the kid was clinging to his father and I think we managed to coax a smile out of him."