This is incredibly lame, but I heard it from a nine year-old...
And it goes like this:
There was this family of Moles in a Mole Hole, tunnelling through the earth, when the Mama Mole goes, [sniff-sniff-sniff] "Hey, I smell something good--it smells like pancakes!"
Then the Papa Mole (who is right behind her) goes, [sniff-sniff-sniff] "I smell bacon!"
Big Sister Mole (next in line) does something similar, like [sniff-sniff-sniff] and says "I smell sausage!"
And finally, Baby Mole, staying true to his birth order profile of being a total ham, plays it for cheap laughs, after the obligatory [sniff-sniff-sniff], then announces,