He was mute and you didn't know how or why it happened, you just knew he was.

He would just text on his phone or write in the notebook and that was how he communicated.

He was a shy guy and you wanted to teach him more convenient way to talk and you introduced him to ASL. He knew the basics and you were there to teach him the rest.

He was all nice and sweet with you and was grateful.

"How do I say 'thank you'?" He asked in his notebook. He had his puppy eyes as always.