Problems with tree and arrows

Question

I am using LyX and I have to create a tree of a stemma codicum. I used a forest package with forest library linguistics. The obtained result is good but I still need to create an arrow linking L to \Gamma. Could anyone help me?

\documentclass[oneside,italian,english]{book}
\usepackage[T1]{fontenc}
\usepackage[latin9]{inputenc}
\setcounter{secnumdepth}{3}
\setcounter{tocdepth}{3}
\usepackage{forest}
\usepackage{amsmath}

\makeatletter
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Textclass specific LaTeX commands.
% Load forest linguistics library, if available
\@ifpackagelater{forest}{2016/02/20}{%
\useforestlibrary*{linguistics}
}{}

\makeatother

\usepackage{babel}
\begin{document}
\selectlanguage{italian}%
\begin{forest}
[$\Omega$, fit=band [[$\varGamma$][V]] [, fit=band[[S][F]][[C][L]]]]]]
\end{forest}
\selectlanguage{english}%

\end{document}

Answer 1

like this?

\documentclass{book}
\usepackage{amsmath}
\usepackage{forest}
\useforestlibrary*{linguistics}

\begin{document}
    \begin{forest}
[$\Omega$, fit=band
    [[$\varGamma$, name=a][V]]
    [, fit=band
         [[S][F]]
         [[C][L,name=b]]]
]%]]
\draw[red,->] (a) to [out=300, in=210] (b);
    \end{forest}
\end{document}

in your code you have to much ].