John Watson could have shown little Albert the white rat many times without any noise following, this could lead to elimination of the fear.
This was a famous experiment by John Watson and Rosalie Rayner for which they received much criticism. The child whose name was "Albert" but is famously known as "Little Albert" moved shortly after the experiment so it was a mystery what happened to him until recently when he was found as “Douglas Merritte” who died before he was found.