Why do my child poses not clip with the adult ones

I also had the same problem. I figure its just ea's way of keeping pervs from doing bad stuff with simulated children. but there is a work around, I had to use the "get sim in" with the pose player. yes I tried it and it worked. had to create all my poses individually for example each person in the family had 3 poses each. on separate pose boxes. I created them all in one blender file by appending all the object files of each sim involved then I saved it after they all lined up, then I removed all the charactors and parts except one and saved with new name for pose and sim, ctrl + z to undo the deletes, deleted the one i saved first then the rest except one saved under that sims name and pose, so they are all in separate files. then saved the blender file with all of them back in with a group pose name (just in case) once they are all separated you can add them to their own pose box sets place the custom item from get sim in (one for each posing in same place) get them all in and then start the poses while its paused so they all start at the same time. only problem was the get sim in or pose player one not sure which was causing errors and crashed my game after the first time it ran through the poses. so I saved them all and who knows maybe I will find a way to put them to use in a future project / animated objects etc.

to be honest it wasn't worth the hassle, if the pose player could just do what get sim in does all by itself without crashing my game after one test.  never to work again I ended up unistalling the game deleting every single file for it just to make sure no ghost files (script mods) were left to cause conflict if I tried it again.  I had had MC command center previously but had removed it before adding the pose player and get sim in.
I always try to keep my mods folder as empty as possible when testing things to avoid conflicts.   so there were no other mods in the mods folder, just my poses, the pose player and the get sim in thingy