Answer:
motherly
Step-by-step explanation:
Hannah's matronly smile and kind advice always comforted her youngest brother.
It isn't wide. Wide is an adjective that means a distance.
It isn't eager. Hannah is not eager. She couldn't comfort someone whose upset if she was bouncing off the walls with an eager attitude.
It isn't beautiful. Beauty doesn't always comfort. She'd had to have more than beauty to comfort a young person.
motherly is another (better) word for matronly. You could describe someone as matronly and mean only that she looks like a grandmother. Motherly is someone putting her wisdom into action and acting like a mother.