Depending on what you really want, you can follow the suggestion of @Qrrbrbirlbel in the comment above to your question, and reach quite fast something that could be used. Of course, having the benefits of a completely defined package is a different kind of thing.
\documentclass[fontsize=14pt, paper=a3, pagesize, DIV=calc]{scrartcl}
\usepackage[utf8]{inputenc}
\usepackage[a4paper,margin=2cm,left=1cm]{geometry}
\usepackage[german]{babel}
\usepackage[german]{translator}
\usepackage{tikz}
\usetikzlibrary{calendar}
\def\defyear{2023}
\def\deffamilysize{4}
\def\boxsize{\dimexpr(\linewidth-3cm)/\deffamilysize}
\begin{document}
\foreach \m in {1,...,12}{
\pagestyle{empty}
\noindent\hspace*{2.98cm}\begin{tikzpicture}
\foreach \person [count=\personcount] in {Paula, John, Peter, Jackie}{ %%% ENTER NAMES
\node[xshift=3cm, draw=black,anchor=west,minimum width=\boxsize,minimum height=1.6em,xshift=\boxsize*(\personcount-1),align=center] {\person};
}
\end{tikzpicture}
\noindent\begin{tikzpicture}
\calendar [%
dates=\defyear-\m-01 to \defyear-\m-last,%
day list downward,%
day yshift=1.6em,%
month label left vertical,%
every month/.append style={yshift=1em},%
day code={%
\node[anchor = east] {\pgfcalendarweekdayshortname{\pgfcalendarcurrentweekday}};
\node[anchor = east, xshift=1.5em] {\tikzdaytext};
\foreach \i [count=\icount] in {1,...,\deffamilysize}{
\node[xshift=2em, anchor=west,draw=black,minimum width=\boxsize,minimum height=1.6em,xshift=\boxsize*(\icount-1)] {};}
}
]
if (Sunday) [red!75!black];
\end{tikzpicture}
\newpage
}
\end{document}

pgfcalendar
/TikZ. I think yours is especially easy to implement with just the right settings starting with theday list downward
style.pocketdiary
context module in the TeXnische Komödie 2/2023. While it does not show a "Familienplaner", it looks very flexible. Maybe worth a shot...