The Barely Visible Bear

Julia is a ten-year old girl to whom a bear, named Mischa, appears… almost visible. He tells her that he’s always been around her to protect her but, now that she’s turned ten, he can reveal himself to her; but only she can see him.
Should she reveal this bear-friend to her family; her friends?; What might be the potential consequences. She does make an attempt to do so but they tactfully tell her that this is her imagination at work. Her parents become concerned due to a few episodes with her on this matter, including one incident at school.
A peak of excitement is reached on a boat ride the family takes off the coast of Florida.