On the boy's bike, is the serial number under the bottom bracket shell or is it by the left rear axle? If it's under the bottom bracket shell, then yes, very early post-war. If it's by the left rear axle, then it's either a '52 or '53. Could well have been a Hornet (now missing the tank and other accessories), or could have been a Standard with the basic guard switched out for the deluxe guard. Once bikes have seen as much action as the pictured one, there's almost no telling what's original and what's been switched out over the years by previous owners.
Cheers, Geoff