How do people squirt milk out of their eyes?

People can squirt milk out of their eyes by using a technique that involves expelling milk that has been held in their mouths through their tear ducts. This is possible because the nasolacrimal duct, which drains tears from the eyes into the nasal cavity, can also allow for milk to be forced out if enough pressure is applied. It's often done as a party trick or for comedic effect, but it requires practice and may not be safe for everyone due to potential irritation or infection.