This patch applies the TK Children faces to the three kids in Falskaar.
Of course, there's not point using this patch unless you have both TK Children and Falskaar installed.
TK Children http://www.nexusmods.com/skyrim/mods/49756/?
Falskaar http://www.nexusmods.com/skyrim/mods/37994/?
This patch doesn't contain any meshes, textures, or scripts. It just changes the actor records of the Falskaar children to use a different head body part from the TK Children mod.
It would make sense to put this patch after the Falskaar and TK Children mods in your load order.