Isn't there some kind of product to use to get rid of tangly, matty hair? Rhianna's hair is a MESS! Her hair is a very fine, maybe cottony coat? I brush her several times a day and she still gets knots . . .I just don't get it?

I'm about ready to shave her down . . .
On the other hand, Brody's hair is awesome . . .he's never had the problems that she has . .
Anyone have any advice on what kind of comb/brush and or product that can be used to reduce the amount of knots she gets?