This is an override that fills in the space between CEP halfling heads pma0_head026 - pma0_head160 (for males) and pfa0_head015 - pfa0_head161 (for females). I simply copied the last CEP head and pasted it multiple times, renaming the head number so it bridged the gap between where the CEP heads ended and the Bioware "children" heads began. So, while these heads do nothing for you in and of themselves, they will now allow you to select the children heads (161-167 for females, and 160-161 for males). Simply place these in your override folder, and you should be good to go.
Note: You must have CEP installed in order to use these heads as the numbering system only works with the CEP head numbering system.
Note 2: The CEP head override can be found here: http://nwvault.ign.com/View.php?view=Models.Detail&id=338 (copy and paste this link to your address bar in your internet explorer ;))