I might not have been paying attention but what happened to the third baby during the switch?
Hiya! :) It is explained in the book (which I very much recommend! :)). If you want to read the book and find out then stop reading now ❤.
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In the book there is more about The Them and we find out that Tadfield as another gang lead by the boy 'Greasy Johnson', the gang is called the Johnsonites. We find out that Greasy Johnson is actually the third baby :). And there are some greats passages about the metaphors for The Them vs the Johnsonites / Hell vs. Heaven :):
"I dunno," said Pepper. "I mean, it wouldn't be so interesting without ole Greasy Johnson and his gang. When you think about it. We've had a lot of fun with ole Greasy Johnson and the Johnsonites. We'd probably have to find some other gang or something."
"Seems to me," said Wensleydale, "that if you asked people in Lower Tadfield, they'd say they'd be better off without the Johnsonites or the Them."
Even Adam looked shocked at this. Wensleydale went on stoically: "The old folks' club would. An' Picky. An'—"
"But we're the good ones . . ." Brian began. He hesitated. "Well, all right," he said, "but I bet they'd think it'd be a jolly sight less interestin' if we all weren't here."
"Yes," said Wensleydale. "That's what I mean."
"People round here don't want us or the Johnsonites," he went on morosely, "the way they're always goin' on about us just riding our bikes or skateboarding on their pavements and making too much noise and stuff. It's like the man said in the history books. A plaque on both your houses."
This met with silence.
"One of those blue ones," said Brian, eventually, "saying 'Adam Young Lived Here,' or somethin'?"
Normally an opening like this could lead to five minutes' rambling discussion when the Them were in the mood, but Adam felt that this was not the time.
"What you're all sayin'," he summed up, in his best chairman tones, "is that it wouldn't be any good at all if the Greasy Johnsonites beat the Them or the other way round?"
"That's right," said Pepper. "Because," she added, "if we beat them, we'd have to be our own deadly enemies. It'd be me an' Adam against Brian an' Wensley," She sat back. "Everyone needs a Greasy Johnson," she said.
"Yeah," said Adam. "That's what I thought. It's no good anyone winning. That's what I thought." He stared at Dog, or through Dog.
"Seems simple enough to me," said Wensleydale, sitting back. "I don't see why it's taken thousands of years to sort out."
And then on the airfield :):
"I just don't see why everyone and everything has to be burned up and everything," Adam said. "Millions of fish an' whales an' trees an', an' sheep and stuff. An' not even for anything important. Jus' to see who's got the best gang. It's like us an' the Johnsonites. But even if you win, you can't really beat the other side, because you don't really want to. I mean, not for good. You'll just start all over again. You'll just keep on sending people like these two," he pointed to Crowley and Aziraphale, "to mess people around. It's hard enough bein' people as it is, without other people coming and messin' you around."
Crowley turned to Aziraphale.
"Johnsonites?" he whispered.
The angel shrugged. "Early breakaway sect, I think," he said. "Sort of Gnostics. Like the Ophites." His forehead wrinkled. "Or were they the Sethites? No, I'm thinking of the Collyridians. Oh dear. I'm sorry, there were hundreds of them, it's so hard to keep track."
