You can also tell the difference from the color of their noses. If the nose it blue it's a male if it's pink it's a girl.
Cere color that is!
Answer.
The only visual way to tell is by the color....
The way i see it you are one of either two kinds of people. One you are really a twisted and perverted individual who thinks that its ok to cheat on your wife or two (which is what i'd put my money...
When they are about 3 weeks, pick them up and turn them onto their back. There is a furry fleshy lump that is visible at the very base of the tail. Move the "lump" toward the tail. You will see...