Milkiin is an illness that some people are born with. It makes people start acting like squirrels until they reach the age of 4. Then, they shrink to the size of a fly at age 20 and grow to the size of a tree at age 25. Then, they go back to normal at age 34. They also puke 3 times a day for the rest of their life.
It was discovered by Swiss physician Arnold Mouse in 1970.