Kamishirasawa-Sensei?

Yes...

He never had a father, and last year his mother finally succumbed to her long term illness...

He's a good kid that never gave in to his impoverished circumstances.

Even when trying to help his mother, whenever he would have free time, he would come to me, asking to be taught.

Possibly due to his family circumstances, he was at odds with the other students at first,

But due to his sunny personality, he's now opened up to everyone.