The stories I most want to know are locked inside my brother Noah. Noah is 20 and he has never spoken a full sentence. He has Down syndrome, and his vocabulary consists of a jumble of grunted words (no, TV, ice cream, hi) and sign language (music, TV, ice cream, more, drink, please). And, perhaps because I rely too much on words, I've always felt that my other siblings had an easier time than I did communicating with him.

I was 15 when Noah was born, two months early and so small my dad could hold him in one hand. He stayed in the hospital for two months, where my siblings and I would squint through the window into the nursery trying to pick him out behind panels of plastic and beeping monitors and webs of cords. Then (we pointed), there he was, his tiny purple chest rising and falling, his body so small they could draw blood only from his heel. I sobbed when I saw the nurse approach him with a needle. His lungs were too small for crying, and I cried for him.

He is big now and easier to pick out in a crowd: tall and blonde with large blue eyes—but I still find myself searching for him, as though by looking at his face, the slope of his shoulders, the turn of his mouth, I could ever find out what is in him—and how much of it is mine to know.

The process of trying to talk to Noah began when he was a baby: He was fitted with hearing aids but hated them. After that, we learned sign language and after that there was the Picture Exchange Communication System, which consisted of laminated pictures of food and drink and TV. Then there was a sort of proto-iPad that repeated words (recorded by my sisters Rebecca and Catherine) whenever he pressed on the corresponding pictures. During visits home from college, I'd ask him ridiculous questions. "Noah, do you want a rhino to sit on you?"

He'd press "No."

I'd press "Yes."

No.

Yes.

Rebecca's robotic voice was arguing with itself and she wasn't even in the room. I would laugh. Noah would smile and pat me on the back. And then, we'd start again.

Now he uses an application on the iPad called Proloquo2toGo, which allows him to press the words he needs to tell us what he wants to eat (French fries and ice cream usually). But sign language, PECs, and the latest app don't help me when I want to talk to him about more than food. Or when he wants to sit with me and watch The Prince of Egypt over and over, rewinding to hear his favorite songs. I will sit as long as I can, asking him questions he never answers.

"Who are your friends at school?"

"What are you learning?"

"Did you go bowling yesterday?"

I hear myself and I hate my voice. I sound so fake. So hopeful for answers I know will only be met with silence or grunts. But what else do I do? I want him to know that I love him and that I miss him. "Did you see Toy Story 2?" I'll ask. He'll nod.

Eventually I will slip away and let another sister take my place. My sisters are better at talking to him anyway.

Ruth was six when Noah was born and lives only seven miles from my parents' house. She tells me that she talks to Noah best through silence. She loves to sit with him as he watches a Disney movie or plays with his Toy Story figurines. When she needs to talk to him, she tells me, she pays close attention to his body language. "Is he rigid or relaxed? I have to pay attention to my own body language as well. If I cross my arms or get tense, he senses that too."

She tells me about times when he's gotten so upset, he began to yell and flail his arms. Ruth says in those moments there is nothing she can say. All she can do is wrap her arms around him until he calms down. The moments that Ruth feels she is really communicating with Noah are the moments when they are just quiet together: "It's in the quiet when Noah is really there," she says.

My sister Rebecca was 10 when Noah was born and she communicates best with Noah through sign language. Rebecca has her master's in social work and spent years taking American Sign Language classes and completed some coursework to become an ASL interpreter. She sings songs for him in church or over the iPad when they FaceTime.

Rebecca also tells me that we each connect to the parts of Noah that we understand best—Ruth knows his silence, Catherine knows his songs, Rebecca knows his hands.

Those are the moments, when she is signing and he is contributing his off-key shouts, when she tells me she really understands him.

Catherine was eight when Noah was born, and the two have grown closer in the past few years. When Catherine was 18, she was in a car accident that shattered both of her legs. She spent a lot of her recovery time at home with Noah. "Noah would just come up and make camp by me, bringing his movie and [toys], drink and snack, then just sit next to me," she told me. "If I was crying he would give me a hug, if I was just sitting blankly staring he would give me one of his [toy] guys."

Catherine says she listens for the emotions behind the sounds Noah makes and, like Rebecca, feels closest to Noah when she sings to him. Catherine lives in Florida now, far away from Noah, who lives in Denver. But they use FaceTime to talk. He will show her a figurine. She will sing him songs. "He shouts along, rocks back and forth dancing with me," she tells me.

Often on visits home, I will witness my sisters and mother arguing over what Noah wants as he sits there watching. Is he amused? Frustrated? My younger brother Caleb, who was three when Noah was born, often shoos them away. "Leave him alone," Caleb will say.

There are so many voices, but none of them the one that needs to speak.

When I ask Rebecca if she ever gets frustrated that we can't hear directly from Noah himself, she rejects the premise of the question. "Whenever you think you can't talk to someone that just means you are deaf to the ways that they are making their voice heard," she says. "Everyone communicates, we just need to learn how to listen better."

Rebecca also tells me that we each connect to the parts of Noah that we understand best—Ruth knows his silence, Catherine knows his songs, Rebecca knows his hands. My brother Zach tells me of a time when he took Noah for a drive and they listened to the band Guster for hours as the wind blew through the car. "He would occasionally look over at me and give me a huge smile and clap his hands and say, 'yay.' But otherwise, he sat quietly and happily. When we eventually parked, we got out and I remember he gave me a hug."

And how do I tend to connect with Noah? I talked to my mom and four of my seven siblings for this story. In every conversation, we laughed remembering silly moments and shared frustrations. Each of my siblings recalls things I've forgotten, moments I missed. They shared these with me, sometimes irritated, sometimes sad, but every time I hung up the phone I felt that, by listening to them, I was finally hearing Noah. My mom often tells us that Noah is never happier than when we are all together. Perhaps that is because each of us carries part of our brother in us. His voice is all of us—shouting, singing, silent, and hands raised. Interviewing them, I felt closer to Noah than I have since I left home 15 years ago.

Noah will come visit me next week and when he is here I will make time to sit with him and sing to him. I will play him music and remember all the sign language my hands have forgotten. I'll watch his eyes, I'll watch his shoulders, I'll keep my mouth shut, and then, maybe, I'll finally talk to him again.