#!/usr/bin/perl
    use warnings;
    use strict;
    
    my $filename = 'pedigree_proband_testfile.txt';
    
    open (FILE, "<", $filename) or die "Cannot open file $!";
    
    my @data = <FILE>;
    my @column;
    my $motherID;
    
    
    
    foreach my $line (@data)
    {
    	@column = split ( /\t/, $line);
    	
    	if ($column[13] eq "" && $column[4] ne "" ) 
    	{
    		$motherID = join($column[2],$column[4]);
    		
    		
    		if ("$motherID" eq "$column[2]")
    		{
    			print "$line\t\n";
    		} 
    	}
    }