I don't clip my cat's nails and I never have. She is inside/outside, so she sort of clips them herself. She sharpens them on cement!!! That has to keep them short. They are fairly sharp, but aren't that long. She is six years old and I don't think that she would let me clip them. She doesn't like it when I hold her paws for a while. Does it matter that I don't clip them, or is there some life threatening illness if I don't?