im sure everyone has either come across this problem but if not then im a fool.

i've modelled a character and am rigging him, its all done apart from the head where the mesh does not follow the bone (i'm using a biped with physique on the mesh) when i move the head, the chin gets left behind. like it's weight on the chin is low, i can get a screen grab if you dont know what i'm talking about

it's irritating because i cant move the guys head without it getting mis-shapen,
please help.

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