Custom Head - Child has missing eyelid piece

Hey there, I'm currently making custom heads for my sims that just remove the ears - and it's going great so far, except for one problem. The child heads seem to lose a piece of their right eyelid in-game - not in blender, not in s4s, strictly in-game. There's nothing to imply that I did something wrong, as the head seems perfectly fine in blender and s4s. I'm not sure what could be wrong?



(Mid-blink screenshot while I was trying to modify the eyes in-game - shape of the eyes is not through editing the head model, it's from the default eye sliders)



The weights:

b__R_UpLid__


b__CAS_R_EyeScale__