I looked it up Cosy… only thing I could find was an interview with Hayley Mills apparently the other kids were just locals not actors at all… about the little chap she says:
To me the greatest character of all is our Charlie (Alan Barnes, one of the locals), who must be five or six, a solemn little lad whose straightforward faith quickly deserts him when “Jesus” fails to work a miracle. “He’s not Jesus, he’s just a fella,” Charlie tells his big sister.
:D :D :D