My friend was playing with her 18 month old son, gently touching every single one of his toes:
“This little piggy went to market,
This little piggy stayed home!
This little piggy had a salad,
This little piggy had none…
And this one cried all the way home: wee-wee-wee!”

The boy giggles. My friend wants to share how well her kid knows all of his body parts:
“What’s this, Joseph?” – she is pointing to his head.
Baby, happily: “Head!”
“What’s this?” – she is pointing to his knees.
“Knees!”
“And… what’s this?” – she is pointing to his toes.
“PIGS!” – proudly announces her little one.