The little girl and the little dog are the best of friends.

He can’t hear and neither can she. They were born that way, locked inside their soundless heads while surrounded by family members who could hear just fine.

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Walter, a Chihuahua-terrier mix, was one of five pups born nine months ago. Julia, who is 10, used to snuggle her face in her mother’s neck when she was a baby, searching for her mom’s soothing scent.

The two were united after Chrissy, Julia’s mom, saw a photo of Walter on the Pasadena Humane Society Facebook page. The wiry, sweet-faced mutt touched her heart.

"I remember just looking at him and I just — I just knew the he was meant to be ours,” the California mother said.

The first time she picked him up, he did just what Julia had done as an infant — he nuzzled her neck.

The puppy had been left at the society, all with his four siblings, by his original owners when all were about six weeks ago. In January, Walter went to live with Julia and her family, who asked that their last name not be used.

But when the society posted a heartwarming video made with 1620 Media of Julia playing with Walter — and teaching him sign language — the two became online reality stars.

The footage has been liked more than 5,000 times since it went up last week.

“Walter and Julia have one amazing bond and I’m glad everyone has taken a liking to it,” Chrissy said.

Walter, Julia says, “is my best friend.”

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He waits for her to finish her homework. She has taught him the sign language word for “sit,” which he does. She also signs the word “water” as she puts his bowl in front of him and signs the word “food” as she hands him something to eat.

“These are my loves and they have taught me that love defines all,” Julia’s mom said.

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