I personally strongly believe she nicked it from Oliver Twist. From the film, specifically, since we all know she buys books not to read but to arrange by spine colour. So she came up with that scenario specifically to plant in her readers' minds an image of angelic SB, his eyes round with hunger, his lower lip trembling slightly, pitifully holding out to her an empty bowl which she cannot fill.I'm starting to wonder whether SB's "more bread and jam please mummy" started life in her head as an ad for her execrable craft enterprise.
A heart wrenching image right? Aaaaand here's my paypal folks! Wouldn't want my kid to go hungry would ya?! Ker-ching!!