Getting multiline nodes automatically with forest

Question

This defines a command that allows multiple lines within a forest node.

\documentclass{article}
\usepackage{forest}
\usepackage{varwidth}

\newcommand\nbox[1]{\begin{varwidth}{.5\textwidth}#1\end{varwidth}}

\begin{document}

\begin{figure}[h]
  \centering
  \begin{forest}
[parent
  [\nbox{first\\child}]
  [\nbox{second\\child}]
  ]
  \end{forest}
\end{figure}

\end{document}

Is it possible to have this command inserted automatically into all nodes, so it does not have to be repeated? This would be useful where all or almost all nodes have multiple lines.

Answer 1

You really do not need varwidth to have multiline nodes. for tree={align=left} does that already.

\documentclass{article}
\usepackage{forest}

\begin{document}

\begin{figure}[h]
  \centering
  \begin{forest}
  for tree={align=left}
[parent
  [{first\\child}]
  [{second\\child}]
  ]
  \end{forest}
\end{figure}

\end{document}