I'm sure it has a lot to do with that, a kitten seperated from the mother that young is just not "finished", so to speak. Usually kittens stay with their mother for 12 - 14 weeks, after that time, the mother will reject it. At that point, the kitten has learned everything for his adult's life from his mother.

Kittens seperated from their mother earlier may have a lack in their socialisation skills, I've noticed that very well in my RB Katz and in Luna. Both have been seperated from their mother at the age of 6 weeks and two days. Both were/are shy animals that only trust one person (me); Katz was very destructive and Luna has litter box problems. Both these girls always seem to be a bit depressed. Both of them had/have a lot of health problems to deal with.

Lily has been with her mother for 11 weeks, and she's everything a cat should be! She's self-assured and relaxed, and she's always in a good mood. I never saw her grumpy or aggressive, she's always friendly. And she hasn't been sick so far.

Kirsten