dig one's heel

Still Aliceの巻末付録 'Excerpt from Lisa Genova's novel Inside the O'Briens' からの引用です。
The youngest thinks they should just let their mom know the information, and she can do with it what she wants. This is pretty common in families where someone has Alzheimer's. There's disagreement and people dig in their heels and take things personally. It's rife with conflict.
慣用句の "dig in their heels" は 6/30/2014" に取り上げました。