a millstone round one's neck

1. 套在身上的沉重负担
   His lazy son is a millstone round his neck.

   他那懒散的儿子是套在他身上的一个沉重负担。

between the upper and nether millstone

1. 上下受夹攻；备受不可抗拒的压力
   He's between the upper and nether millstone.

   他深受上下夹攻。