AMonarch
No matter how kind and patient a person is, at some point, they will snap if pushed too far. I understand tht Yuki is still young but he should've not raised his voice even if he dislikes the situation. It's not possible that he didn't notice how hard-working her mother was, but most importantly, he must've noticed that he didn't have a 'father'. That should already be a strong enough hint for him to notice their family situation. So, I'm pro mother in this chapter