When they're about to tuck in to a mouth watering plate of bangers and mash (you know, the mountain of mash with sausages sticking out of the side), or an ice cream the size of a house, or a big chocolate bar...
You see them dribbling and there's a big caption in the cartoon frame going "SLLLUUUUUURRRRP"
Lovely toy..got some brand new (and cheap!!) spare side panels, air conveyors and front mudguards coming in if you fancy some spares (no longer available from dealers).