A pair of dognappers snatched up a dachshund named Milkshake from a Bronx apartment – while the emotional support service pup’s owner was distracted with her young son’s birthday party, authorities said Wednesday.

A young man and woman stole the 10-year-old female pooch – which her owner Luz Montanez, 34, called her “baby” and “soulmate” – from inside a building on Tiffany Street near Westchester Avenue in Longwood on May 4, according to cops and surveillance footage of the pair. 

“People who are dog people don’t do things like what they’ve done,” Montanez told The Post in a phone interview. “It’s mean, and nobody does that. I know your intentions for the dog are not pure.” 

“I need someone to hear me because she needs to come home. She needs to come home already,” Montanez said in a desperate plea.

Montanez said she was hosting a Bluey-themed birthday party inside the apartment for her kindergartener son, and had let the kids outside to play. Milkshake later joined them, she said. 

By around 7:50 p.m., as Montanez served cake to the guests, she realized the brown pup was gone. 

“Usually Milkshake is always at my ankles, because you know, she’s looking for a snack,” Montanez said. “She hears ruffles in the kitchen and she’s like, ‘Food!’”

“So I realized like, ‘Wait where’s Milkshake?’ And immediately I’m thrown into panic and anxiety.”

It wasn’t long before it became clear that Milkshake was stolen.

“Milkshake knows where lives,she knows how to stand at the front door,” Montanez said. “She knows how to stay parked at the front door of our building.

“So this is just odd. She doesn’t wander.”

Video released by the NYPD Wednesday morning shows the pint-size dog following the two thieves along the hallway, up and down a small flight of stairs and toward the door. 

Montanez said the suspects “look familiar,” but she does not know them personally.

In the weeks since the caper, Montanez’s young son has asked her about Milkshake’s whereabouts and “why they took her,” she said.

“I don’t know if anyone’s ever been like really low and if you’ve ever had your little child patting you on the back, saying, it’s OK,” she said. “That is such a heartbreaking moment.” 

Milkshake had not been returned by Wednesday, and no arrests had been made. 

By now, Montanez said, someone with good intentions would have returned the pup. 

“She’s not a stray – she’s tagged up like, why wouldn’t you just call the person like, ‘Hey, we found your dog in the hallway. Are you missing her?’” she said. “Like, I just don’t understand the non-human, [lack of] decency.”

Montanez said Milkshake was only 3 weeks old when she received her – as a birthday present from her dad – and even bottle-fed her and kept her baby teeth in a jar.

“Milkshake is legit the first child. I call her my favorite,” the distraught owner said. “I mean, both of my kids are my favorite… I tell her, ‘You’re my favorite dog. And I tell my [son], ‘You’re my favorite human.’ These are both my kids!”

“This is my baby. This is my soulmate,” Montanez added of her beloved pet. “This is my heart, my heartbeat. She’s been through everything with me.”

“When my husband was deployed, she was there. When I got pregnant, she was there,” she said. “I’ve been through accidents, car accidents, she’s been there. She’s my everything. This is my baby – my first baby – the thing that taught me responsibility in life.

“Yeah, she’s the type of dog like she sees me upset, she’s sitting next to me and she’s gonna lick my tears.”

Now, she says, she’s only urging the cruel dognappers to “bring her home.”

Anyone with information on Milkshake’s whereabouts, or the suspect, is asked to call the NYPD’s Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).

The public can also submit their tips by logging onto the Crime Stoppers website at https://crimestoppers.nypdonline.org/, on Twitter @NYPDTips.