HunchBluntley: [sighs] Really? No one else? Fine, make me break character...[grumble grumble]...
He meant to type "[they] don't know they're born", which seems to be an almost exclusively British phrase (not sure if it's used in Ireland). I've heard it before, but not often, and I've always been left to guess the meaning from the context; some of the responses in this very old (but still relevant) thread seem to answer that question well enough.