Some simple code:

use warnings;
use strict;

my %birthdays = (
                     Fred   => 'June 1',
                     Ray    => 'May 31',
                     Glenn  => 'May 27',
                     Bob    => 'August 28',
                     Jim    => '',
                     Paul   => undef,
                );

foreach my $name ( sort keys %birthdays) 
{
   next unless defined $birthdays{$name}; #skip undef
   next if $birthdays{$name} eq '';       #skip blank
  
   print "$name $birthdays{$name}\n";
}



__END__
Bob August 28
Fred June 1
Glenn May 27
Ray May 31
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