I too saw that episode last night and I didn't know where the reference was from either, but my girlfriend swears it comes from a movie in which a group of people are in Australia, camping near a famous rock (her words, not mine), supposedly people go to Australia to see this rock. And she leaves her baby in the tent. Later she hears it crying and sees a Dingo leaving the area around the tent with what looked like a piece of the baby's jacket in its mouth. Well, the people with her accuse her of making up the story about the dingo, while she swears it is true. Anyway, there is a man in the scene who says the line "Maybe the Dingo ate your baby".
Now I don't know if this is altogether correct, but that's what I'm told.