\centering
    \scalebox{0.6}{
    \begin{tikzpicture}
    % Define the box
    \node[draw=brown, thick, rounded corners, text width=\boxwidth, minimum height=7.5cm, inner sep=10pt] (box2) 
    {\centering
        % Heading
        \textbf{PTSD: Concept 9} \\
        % Draw a horizontal line
        \tikz \draw[brown, thick] (0,0) -- (\linewidth,0);\vspace{1em}
        \fixheightbox{
 extremely frequent \highlight{flashbacks} the \\
 me bad. The \highlight{flashbacks}\\
 When I was \highlight{molested}\\
 have vivid \highlight{flashbacks}. All\\
 about \highlight{flashbacks}.
I\\
 after i was \highlight{sexually assaulted}\\
 young child, was sexually\\
 having nightmares and \highlight{flashbacks}\\
 \highlight{repressed memories} are a\\
 because I have \highlight{flashbacks} several\\
 always thought the \highlight{memories}\\
 of scolding via email\\
 like I was \highlight{abused}.\vspace{-5em}
        }
    };
\end{tikzpicture}}