I highlighted my hair and want to dye it a dark brown. Will the dark brown eventually fade out or will it stay that color till it grows out? I dyed it with a brown color that washes out and I am waiting on it to fade out before I try this. I want to color it to hide the bleached highlights till they grow out.

Hair dye can fade but in my experience it normally doesn't unless you are going from blonde to red. Auburn has a tendency to fade easily, but other colors normally shouldn't.