"Little piggy"

TOE

Count from the start of your foot to find this tiny body part.

The phrase "little piggy" comes from the nursery rhyme "This Little Piggy", where each line refers to a toe—starting with the big toe as the "little piggy" that went to market. Here, the clue plays on that familiar childhood reference to hint at a body part. Since the rhyme is all about toes, the answer is simply "TOE," with no extra wordplay needed.