Crusty Stuff in Cats Eyes

Question
Hello-
One of my cats has black crusty stuff in her eyes all the time. I clean them out for her with warm water and although they don't bother her at all I am concerned. She has always had crusty eyes, her sister doesn't though. Her eyes are clear and there is no discharge coming from them. She just has black/brown crusty stuff in the corners. It doesn't bother her to have them cleaned out even if they are stuck.  Anyway, does she need to be seen by a vet or is this just how her eyes are? Also she is just a domestic shorthair. Thanks for your help. Tori  

Answer
This is most likely just "eye booogers" and your one cat may not be very particular about cleaning her eyes herself.  If she is eating normal, not having any coughing and sneezing and the discharge is not green or yellow, you can just continue cleaning her eyes as you are.  If anything changes, then take her to the vet.