Fear is our brain's tool to protect us and to be cautious, it is practically what motivates us to look for solutions, it has not preserved subsistence over time. But also, fear has not inhibited us from doing things, it is only those daring people who have overcome their fears who have achieved great things in life. Little Smallsteps is at that stage of questions and answers, she is eager to discover the world and is therefore afraid of the new. The important thing is that she has parents who have managed to handle the situation and are giving her the necessary guidance to survive the concrete jungle.
Fear is a builder in this sense too - where it makes us prepare for an unknown future. Fear is felt in the moment, but it is based on what could happen. Even if a hungry tiger is chasing, the fear is of being caught and eaten in the future - though it isn't very far in the future.