  A planar semimodular lattice $K$ is \emph{slim} if $\mathsf{M}_{3}$ is not a
sublattice of~$K$. In a recent paper, G. Cz\'edli found four new properties of
congruence lattices of slim, planar, semimodular lattices, including the
\emph{No Child Property}: \emph{Let~$\mathcal{P}$ be the ordered set of
join-irreducible congruences of $K$. Let $x,y,z \in \mathcal{P}$ and let $z$ be
a~maximal element of $\mathcal{P}$. If $x \neq y$ and $x, y \prec z$ in
$\mathcal{P}$, then there is no element $u$ of $\mathcal{P}$ such that $u \prec
x, y$ in $\mathcal{P}$.}
  We are applying my Swing Lemma, 2015, and a type of standardized diagrams of
Cz\'edli's, to verify his four properties.
