My Daughter Is 1 And Has What I Call An

My daughter is 1 and has what I call an "outie" belly button. Sometimes it's red and raw looking, may have little crusties that are yellow colored, and smells terrible. I've been putting neosporin on it. Sometimes when I try to clean it or doctor it she cried like it burns and hurts. What could be causing this and how should I treat it? It's not that way all the time just every few weeks or so and then clears up within a week. Any advice??