Swim And Ride

Two young boys walked into a pharmacy one day and picked out a box of Tampax.  They proceeded to the checkout counter to pay.

The man at the counter asked the older boy, "Son, how old are you?"

"Eight", the boy replied.

The man continued, "Do you know what these are used for?"

The boy replied, "Well... not exactly, but they aren't for me.  They are for my brother and he's four.  We saw on TV that if you use these, you'd be able to swim and ride a bike.  He can't do either yet."