my $testarray = [
                 { messageId => 1,
                   parent    => 1 },
                 { messageId => 2,
                   parent    => 1 },
                 { messageId => 3,
                   parent    => 1 },
                 { messageId => 4,
                   parent    => 2 },
                 { messageId => 5,
                   parent    => 3 },
                 { messageId => 6,
                   parent    => 2 },
                 { messageId => 7,
                   parent    => 4 }
                 ];