\documentclass{article}

\usepackage{tikz}
      \tikzstyle{invisible} = [outer sep=0,inner sep=0,minimum size=0]
      \tikzstyle{bordered} = [draw,outer sep=0,inner sep=1,minimum size=10]
\begin{document}

      \begin{tikzpicture}
      \node[invisible] (v2) at (0,-1) {};
      \node [bordered] (v1) at (0,0) {root root root};
      \node [bordered] (v3) at (3,-1) {ABC1};
       \node [bordered] (v4) at (-3,-1) {ABC2};
      \draw [line width=1mm] (v1) edge (v2);
      \draw[line width=1mm] (v2) edge (v4);
       \draw [line width=1mm](v2) edge (v3);
        \node [bordered] (v5) at (3,-2) {ABC3};
        \node [bordered] (v6) at (3,-3) {ABC4};
          \node [bordered] (v7) at (3,-4) {AB54};
            \node[invisible] (v8) at (0,-2) {};
            \node[invisible] (v9) at (0,-3) {};
            \node[invisible] (v10) at (0,-4) {};
 \draw  [line width=1mm] (v8) edge (v2);
\draw [line width=1mm]  (v8) edge (v9);
\draw  [line width=1mm] (v9) edge (v10);
\draw  [line width=1mm] (v7) edge (v10);
\draw [line width=1mm]  (v9) edge (v6);
\draw  [line width=1mm] (v8) edge (v5);
\end{tikzpicture}

\end{document}