# Vertical links between middle parts of ganttbars in pgfgantt

I have two ganttbars in a gantt chart using pgfgantt. I want to show that "at this point, the work from here will influence the other part of the project" by making a link that goes from the bottom of a ganttbar to the top of another one at a given time point. Is there a way to do this?

A toy that one may have is the following:

\begin{ganttchart}[y unit chart=.7cm]{1}{12}
\gantttitle{2020}{12}

\gantttitlelist{1,...,12}{1}

\ganttbar{Project 1}{1}{9}
\ganttbar{Project 2}{4}{12}

\end{ganttchart}


I want to show that at Month 5, Project 1 will give lead to information for Project 2. Is there a link that makes this possible?

Most likely I do not understand the question. But perhaps this can be the basis for an answer. Yes, you can link bars.

\documentclass[border=3.14mm,tikz]{standalone}
\usepackage{pgfgantt}
\begin{document}
\begin{ganttchart}[y unit chart=.7cm]{1}{12}
\gantttitle{2020}{12} \\
\gantttitlelist{1,...,12}{1}\\
\ganttbar{Project 1}{1}{9}\\
\end{ganttchart}
\end{document}


But from your description I am wondering if you are looking for a milestone at month 5 which should be linked.

\documentclass[border=3.14mm,tikz]{standalone}
\usepackage{pgfgantt}
\begin{document}
\begin{ganttchart}[y unit chart=.7cm]{1}{12}
\gantttitle{2020}{12} \\
\gantttitlelist{1,...,12}{1}\\
\ganttmilestone{}{5}
\ganttbar{Project 1}{1}{9}\\
\ganttmilestone{}{5}
\ganttbar{Project 2}{4}{12}