Answer:
A person's greatest asset.
Hot tempered and sometimes it blows its top, making a mess of everything.
I question what lies above, and Iβm shared with those you love. At my sound your hands will shake, and oft heard soon after wake. A card not found in a deck.
Without what would everyone lose their head?
Lovely and round, I shine with pale light, Grown in the darkness, a ladyβs delight.
What is full of holes but still holds water?