c:\@Work\Perl\monks>perl -wMstrict -le
"use strict;
 use warnings;
 ;;
 use Data::Dump qw(dd);
 ;;
 my %son_father;
 ;;
 my $name1   = 'Jeff';
 my $add_dad = 'Doug';
 ;;
 $son_father{$name1} = {$add_dad};
 ;;
 dd \%son_father;
"
Odd number of elements in anonymous hash at -e line 1.
{ Jeff => { Doug => undef } }