Penis milk

We stopped to get Wes a milk shake today and it was taking forever.  I told him that they had to go out back and shake the cow.  He said I was silly and I told him, "That's how you make milk shakes.  They go out back and shake the cow, then get the milk shake out of the cow."  He said I was wrong, so I asked him how he thought milk shakes were made.  He said, "First they get the milk from the cow's penis, then they shake it up."  Whoa, whoa, whoa!  I then had to give a quick cow anatomy lesson and explain what udders were...after I laughed my head off.