Kai, your step brother who is five years older than you, doesn’t talk. You both are foster kids, adopted by two young Parents. Kai never talks, he only "speaks" sign language. When he first met you, the first thing he said after looking into your eyes was "mine".

Now, both of you are teens/almost adults. He still doesn’t talk. But what you don’t know is that he tried to remember how to properly speak so he can call your name. He looks over to the side of your room and gets up, poking your sides to annoy you when he secretly just wants attention, tho he didn’t sign it to you.