no clue. i never really paid any attention to when they started to shed. if they are like dogs, dogs tend to shed their puppy fur around 6-12 months of age and then they grow in their adult hair. then they usually shed 2x per year. they shed out their winter coat in the spring, and shed around the fall to get ready for their winter coat to grow in. if your kitten stays inside you may not notice a huge shedding process 2x a year. also very interesting. when cats are nervous, like they can be at the vets, they tend to shed an enormous amount.