Very normal. This is the time of year I used to brush Casey daily. Otherwise my house would be covered with her hair. She would shed a lot! I sometimes wondered where all of the hair was coming from. I think as I would brush some out new ones would grow in.

I have been combing the cats a couple times a week too. Mack gets combed everyday. Even though he is a short hair cat, I don't think he grooms himself like the other 3. Luckily he LOVES the comb.