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On August 10, TikTok user @cincygirl513 shared a video of her son opening his birthday presents, and his sweet reaction quickly went viral.

According to the text overlaying the start of the video, which shows the boy carefully opening a present covered in shark-themed gift wrap, he's been begging for a dog since he was three years old.

"Oh my goodness," he said as he finally freed the first gift—a Stranger Things-branded walkie-talkie.

"It's cool, right? It's Stranger Things, right? That's what you like?" his mom asked from off-camera.

"Yes," he answered happily, looking over the toy—which is clearly not a real walkie-talkie—with a smile on his face.

At that point, the text on the screen changed to say, "It's his 12th birthday today and we couldn't be more proud of this kid…"

"What's the other thing?" his mom asked, calling the boy's attention back to the package on the counter. He squeaked the first present—a dog toy—as he placed it on the counter, causing his mother to ask again, "What is that?"

"These are dog toys," he told her gently, moving easily onto the next gift: a stuffed basketball.

"Are you serious? They're dog toys?" his mother feigned ignorance well, sounding like she felt awful for the mix-up. "Oh my God, ugh," she sighed. But as he kept squeezing the basketball, the smile never leaving his face, a man presumed to be his father snuck up behind him, cradling a puppy in his arms.

"His wish came true 🥰❤️," the text changed again as she continued, "I'm so sorry, Bud. I guess you need a dog."

You could see the realization click in his eyes just before he turned to see the man and puppy, which looks like a little black lab, standing right next to him. He dropped the toys and gasped, backing away in shock.

"Oh my gosh! I'm gonna cry," he said.

"It's okay," his mom answered before the boy broke down in tears. She gave him a few seconds to collect himself before encouraging him to go say hi to his new pet.

There are several aspects of the post that captured the attention of TikTok. For one, the boy's gracious reaction to his mother "mistakenly" purchasing dog toys for his birthday, acting thankful for the presents even though he didn't think he'd be able to do anything with them.

"What a sweet soul!! Happy Birthday 🥰," one commenter wrote.

"He didn't even care that they were dog toys before he knew the dog was part of it, what a sweet boy," another said.

"The fact he didn't even question/get upset they were dogs toys 🥺😭," someone else added.

Commenters also loved the boy's openly emotional response to the dog, and his mother encouraging it.

"I love the "that's ok" when he said he was going to cry. Small moment, big impact🥰," pointed out one viewer.

"The fact that you immediately told him it was okay to express his emotions and cry is such good parenting," another agreed.

In just one day, the video has been viewed 20 million times and racked up over four million likes. Many commenters are also begging for an update on the new best friends, but the family has yet to post anything else.